Project Controls Glossary · SOMA Project Controls

116 entries

A

AACE 11R-88 (EVMS)

AACE International's Recommended Practice on Required Skills and Knowledge of an Earned Value Management System — the reference for what an EVMS implementation should contain.

AACE 18R-97 (Cost Estimate Classification System)

AACE Recommended Practice defining a five-class cost estimate classification system based on level of project definition, end usage, methodology and expected accuracy range. The most widely cited estimate classification standard across UK and international capital projects.

AACE 57R-09 (Integrated Cost and Schedule Risk Analysis)

AACE International Recommended Practice for integrated cost-schedule risk analysis using the Risk Driver method — discrete risks that simultaneously affect multiple activities, modelled via Monte Carlo simulation of the CPM network.

AACE 113R-20 (Integrated Cost and Schedule Risk Analysis — Parametric and Expected Value)

AACE Recommended Practice for integrated cost-schedule risk analysis using combined parametric cost estimating with expected-value risk treatment. An alternative to 57R-09's Risk Driver method, preferred where parametric cost data is the primary input.

AACE International

The Association for the Advancement of Cost Engineering — the global professional body whose Recommended Practices are the reference standard for project controls, cost engineering and risk analysis.

AMP (Asset Management Period)

The five-year regulatory cycle within which UK water companies plan, fund and deliver capital investment, governed by Ofwat's price review process.

As-Built Schedule

A retrospective schedule showing what actually happened on a project — the real start and finish dates of every activity — used primarily for delay analysis and dispute evidence.

As-Planned Schedule

The schedule showing what the project intended to do at a specific reference point — typically the baseline at contract signature, used as the starting point for delay analysis.

B

Baseline Execution Index (BEI)

A schedule health metric that compares the number of activities completed to the number that should have been completed by the data date, per the baseline.

Baseline Schedule

The formally approved version of the project schedule, against which actual progress and performance are measured throughout the project.

BCWS / BCWP / ACWP

The three foundational EVM measurements — Budgeted Cost of Work Scheduled, Budgeted Cost of Work Performed, and Actual Cost of Work Performed — now usually called PV, EV and AC.

BetaPERT Distribution

A flexible version of the PERT distribution where the weighting of the most likely value can be adjusted, used in advanced quantitative risk models.

Budget at Completion (BAC)

The total approved budget for the project — the sum of all budgets assigned to the work breakdown structure.

C

CADMID

The UK MoD's six-phase acquisition lifecycle. For project controls practitioners — what each phase demands: QRA at Concept, EVMS at Manufacture, through-life cost tracking In-Service.

CADMID Lifecycle

How CADMID's six phases shape the controls function — QRA and cost confidence at Concept, full EVMS at Manufacture, through-life cost tracking In-Service. Gateway tests and failure modes at each transition.

CDM Regulations 2015

The Construction (Design and Management) Regulations 2015 — UK statutory health and safety framework allocating design and management duties to Clients, Principal Designers, Principal Contractors and duty holders on construction projects.

Concurrent Delay

The situation where two or more delay events — one caused by the Employer and one caused by the Contractor — affect the same period of project time, creating a disputed entitlement to time and cost.

Contingency vs Management Reserve

Contingency covers known unknowns inside the project budget; management reserve covers unknown unknowns above it. A practitioner guide to the difference, who controls each, how drawdown works, and why conflating them obscures real performance.

Control Account

A management control point in an EVM system where scope, schedule, and budget are integrated and performance is measured.

Correlation in QRA

The statistical relationship between risks or activity durations in a quantitative risk model — ignoring correlation typically underestimates total project risk.

Cost Breakdown Structure (CBS)

A hierarchical breakdown of all project costs, organised by cost type or element rather than by deliverable — the cost-focused counterpart to the WBS.

Cost Performance Index (CPI)

An EVM metric that measures cost efficiency: CPI = Earned Value ÷ Actual Cost. Below 1.0 means the project is spending more than the work is worth.

Cost Risk Analysis (CRA)

A probabilistic assessment of project cost that models uncertainty in estimates and discrete cost risks to produce a range of possible outturn costs.

Critical Path Length Index (CPLI)

A forward-looking DCMA schedule metric that compares the time available to the time needed to complete the project — below 0.95 signals schedule pressure.

Critical Path Method (CPM)

A scheduling technique that identifies the longest sequence of dependent activities through a project — the path that determines the earliest possible finish date.

Critical Path vs Critical Chain

Critical Path Method (CPM) sequences activities by logic dependencies. Critical Chain Project Management (CCPM) extends CPM by also constraining for resource dependencies, treating shared resources as the binding factor.

Criticality Index

The percentage of Monte Carlo iterations in which an activity lies on the critical path. A probabilistic measure of how often an activity actually drives project completion, used in QSRA / risk-loaded schedule analysis.

D

DCMA 14-Point Assessment

A standardised schedule health check that scores a programme against 14 measurable criteria to test whether it is logically sound and fit for use.

DCMA-14 vs Schedule Quality Metrics

DCMA-14 is a specific 14-point assessment framework developed by the US Defence Contract Management Agency. "Schedule quality metrics" is the broader practice of testing schedule health — which DCMA-14 is one (widely-adopted) instance of.

Disruption (vs Delay)

Disruption is loss of productivity on activities that still complete on time — distinct from delay, which extends project completion. Often claimed separately and requires different evidential approach.

E

Earned Schedule (ES)

A time-based extension of EVM that addresses the limitations of Schedule Variance and SPI once a project passes its planned completion date — giving a more reliable schedule performance measure late in delivery.

Earned Value (EV) vs Planned Value (PV)

EV is the budgeted value of work actually completed; PV is the budgeted value of work that was planned to be complete by now — the gap between them measures schedule performance.

Earned Value Management (EVM)

A performance measurement technique that integrates scope, schedule, and cost to give an objective picture of where a project really stands.

Earned Value vs Earned Schedule

Earned Value (EV) measures schedule performance in cost units and converges to zero at project end. Earned Schedule (ES) measures schedule performance in time units and stays meaningful through the entire project lifecycle.

Estimate at Completion (EAC)

A forecast of the total expected cost of the project based on actual performance to date and any revised estimate for remaining work.

Estimate to Complete (ETC)

The expected cost to complete all remaining project work from the current data date to the end.

Expected Monetary Value (EMV)

The probability-weighted average cost or benefit of a risk event, calculated by multiplying the probability of occurrence by the financial impact.

Extension of Time (EOT)

A contractual mechanism by which the Contractor's completion date is extended to reflect delays caused by Employer-risk events — protecting the Contractor from liquidated damages for excusable delay.

F

FEED (Front-End Engineering Design)

The engineering and design phase that follows concept development and precedes Final Investment Decision — typically when cost and schedule estimates are matured to Class 2-3 accuracy for project sanction.

FID (Final Investment Decision)

The formal commitment by a project sponsor to proceed with execution — the point at which capital is committed based on the FEED-stage cost, schedule and risk position.

Finish-to-Finish (FF) Logic

A dependency type where the successor activity cannot finish until the predecessor has finished — useful for work that must be completed together.

Finish-to-Start (FS) Logic

The most common dependency type: the successor activity cannot start until the predecessor has finished.

Float (Total Float and Free Float)

The amount of time an activity can be delayed without pushing back the project end date (total float) or its immediate successor (free float).

Float Ownership

The contractual question of who owns the slack in a project schedule — whether the Contractor can use float to absorb their own delays, or whether it belongs to the Client.

Free Float

The amount of time an activity can be delayed without delaying the early start of any of its immediate successors.

H

Hammock Activity

A summary activity whose start and finish dates are driven by the earliest start and latest finish of the activities it spans, rather than by its own logic.

Hard Constraint (Mandatory Constraint)

An imposed date in a schedule that overrides the calculated logic — the activity must start or finish on, before, or no earlier than a specific date regardless of network dependencies.

HM Treasury Green Book

The UK government's guidance on appraisal and evaluation of policies, programmes and projects — setting the methodology that public-sector business cases, QRA and cost estimates must follow.

I

Inherent Risk vs Residual Risk

Inherent risk is the exposure before any mitigation; residual risk is what remains after mitigations have been applied. Both should be recorded in the risk register.

Integrated Cost-Schedule Risk Analysis (QCSRA)

A single Monte Carlo model that analyses schedule and cost risk together, capturing the way schedule slip drives prolongation cost and cost pressure drives schedule compression.

IPA Gateway Review

A structured independent review of a UK public-sector major project by the Infrastructure and Projects Authority at defined decision points — testing deliverability, affordability and readiness to proceed.

L

Lag

A positive delay built into a dependency relationship, representing a mandatory waiting period before the successor activity can begin or finish.

Lead

A negative lag that allows a successor activity to begin before its predecessor has finished — generally discouraged and flagged as non-compliant by DCMA 14.

Level of Effort (LOE) Activity

A schedule activity whose duration is determined by the span of other activities it supports, rather than by the volume of work it contains.

Look-Ahead Schedule

A short-range detailed schedule — typically two to six weeks — that extracts imminent work from the master programme for day-to-day site management and coordination.

M

Measured Mile Analysis

A disruption analysis technique that compares productivity during an undisrupted period of the same project against productivity during a disrupted period — isolating the productivity loss attributable to disruption.

Merge Bias

The tendency for a schedule to underestimate duration at points where multiple paths converge, because any one of those paths running late will cause delay.

Milestone

A zero-duration activity in a schedule that marks a significant event, completion point, or contractual obligation.

Monte Carlo Simulation

A computer-based technique that runs thousands of possible project scenarios to produce a probability distribution of cost or schedule outcomes.

N

National Audit Office (NAO)

The UK's independent public-spending watchdog — auditing how government departments and major programmes deliver value for money and reporting findings to Parliament.

Near-Critical Path

A path through the project network with low (but non-zero) total float — close enough to critical that any slip on it can promote it to the critical path. DCMA 14-point assessment monitors activities with ≤7 working days of float as near-critical.

NEC4 Accepted Programme

The current, contractually recognised programme under an NEC4 contract — the reference against which progress, compensation events and extensions of time are assessed.

NEC4 Clause 31 (Programme Submission)

The NEC4 clause that requires the Contractor to submit a programme for acceptance — defining what the programme must contain and how the Project Manager responds.

NEC4 Clause 32 (Revising the Programme)

The NEC4 clause that requires the Contractor to revise the Accepted Programme at defined intervals — keeping the contractual reference programme current throughout delivery.

NEC4 Compensation Event

Under NEC4, a defined event that entitles the Contractor to additional time, cost or both — assessed against the Accepted Programme in a structured, contemporaneous process.

NEC4 Early Warning

A contractual obligation under NEC4 to notify the other party of any matter that could affect price, completion, Key Dates or performance — designed to surface problems while they can still be managed.

NEC4 Key Date

A contractually-binding interim milestone under NEC4 — a point at which the Contractor must complete specific Condition for the Project Manager to be able to proceed with the next activity.

NEC4 Sectional Completion

A mechanism under NEC4 that allows the works to be handed over in defined Sections, each with its own Completion Date and associated rights and obligations, rather than as a single completion event.

NEC4 Target Cost (Option C)

An NEC4 pricing option where the Contractor is paid actual cost plus Fee, with a target cost agreed up front and gain or pain shared between the parties based on the final outturn.

O

Optimism Bias

The well-documented human tendency to underestimate the cost and duration of projects, particularly in the early stages.

Organisational Breakdown Structure (OBS)

A hierarchical breakdown of the project organisation by who is accountable for delivering work — the people-side counterpart to the WBS.

P

P50 / P80 / P95 (Confidence Levels)

Probability thresholds from a risk analysis: P50 means a 50% chance of finishing by that date or within that cost; P80 means an 80% chance, and so on.

Performance Measurement Baseline (PMB)

The integrated time-phased budget for the project, combining scope, schedule, and cost into the reference plan against which EVM is measured.

PERT Distribution

A probability distribution based on the PERT formula that gives greater weight to the most likely value, producing a smoother, more realistic shape than the triangular distribution.

Post-mortem (Lessons Learned Review)

A structured review conducted after a project or phase to capture what went well, what went wrong, and what should be done differently next time.

Pre-mortem

A risk identification technique where the team imagines the project has already failed and works backwards to identify what caused it.

Primavera P6

Oracle's enterprise project and portfolio scheduling software — the standard scheduling tool on UK major infrastructure, defence and rail programmes.

Project Controls Engineer

A practitioner responsible for planning, cost management, risk analysis, and integrated reporting on a capital project or programme — typically chartered through APM, ACostE, AACE or IRM.

Q

QCRA (Quantitative Cost Risk Analysis)

A Monte Carlo simulation of a project cost estimate that produces a probability distribution of outturn cost, rather than a single deterministic figure.

QSRA (Quantitative Schedule Risk Analysis)

A Monte Carlo simulation of a project schedule that produces a probability distribution of completion dates, rather than a single deterministic forecast.

Quantitative Risk Analysis (QRA)

A numerical assessment of project risk that produces probability-weighted cost and schedule outcomes rather than red/amber/green ratings.

R

Residual Risk

The risk exposure that remains after mitigation actions have been applied — the risk the project carries even after doing everything reasonable to reduce it.

Resource Breakdown Structure (RBS)

A hierarchical breakdown of all project resources — people, plant, and materials — organised by type, used for resource planning and cost allocation.

Resource Levelling vs Resource Smoothing

Resource levelling adjusts the schedule to stay within resource limits, potentially extending the project; resource smoothing adjusts resource use without extending the project end date.

Responsibility Assignment Matrix (RAM)

A matrix that crosses the WBS with the OBS to identify who is responsible for each piece of work — the formal basis for control account ownership in EVM.

RIBA Plan of Work

The Royal Institute of British Architects' standard framework for the UK construction project lifecycle — defining eight stages from strategic definition through to in-use, each with its own outputs and gateway criteria.

Risk Appetite Statement

A formal declaration by an organisation of the amount and type of risk it is prepared to accept in pursuit of its objectives.

Risk Appetite vs Risk Tolerance

Risk appetite is how much risk an organisation is willing to seek out; risk tolerance is the maximum level of risk it can absorb before it must act.

Risk Breakdown Structure (RBS)

A hierarchical classification of project risks by source or category, used to organise the risk register and identify gaps in risk identification.

Risk Mitigation Plan

A documented set of actions designed to reduce the probability or impact of a specific risk — linked to the risk register, owned by an accountable individual, and tracked for completion.

Risk Owner

The named individual accountable for managing a specific risk — responsible for monitoring it, implementing mitigation actions, and reporting status through the risk governance cycle.

Risk Register

A structured log of identified project risks, recording what could go wrong, how likely it is, what the impact would be, and what is being done about it.

Rolling Wave Planning

A progressive-elaboration planning technique where near-term work is planned in detail and later work is kept at summary level until scope becomes clearer.

S

S-Curve

A cumulative cost or progress curve that typically forms an S-shape over the project lifecycle, starting slowly, accelerating through execution, then tapering at handover.

Safran Risk

An enterprise-grade schedule and cost risk analysis tool widely used on UK defence, nuclear and infrastructure programmes for Monte Carlo QRA against integrated Primavera P6 or Microsoft Project schedules.

Schedule Performance Index (SPI)

An EVM metric that measures schedule efficiency: SPI = Earned Value ÷ Planned Value. Below 1.0 means the project is behind plan.

Schedule Quality Metrics

The broader discipline of assessing whether a programme schedule is fit to be relied upon — covering structural integrity, resource feasibility, baseline drift, probabilistic readiness and earned-value compatibility. DCMA 14 is the best-known framework, but only one entry point.

Schedule Risk Analysis (SRA)

A probabilistic analysis that models uncertainty in activity durations and discrete schedule risks to produce a range of possible project completion dates.

SCL Delay and Disruption Protocol

The Society of Construction Law's guidance on managing and analysing delay and disruption claims on construction contracts — widely referenced in UK courts, adjudication and expert reports.

Secondary Risk

A new risk that arises as a direct result of implementing a risk response — a side-effect of the mitigation itself.

Sensitivity Analysis (Tornado Chart)

An analysis that identifies which risks or uncertainties have the greatest influence on project cost or schedule outcomes — typically displayed as a ranked bar chart.

Soft Constraint (Preferred Constraint)

A scheduling preference rather than a mandatory date — the tool will try to honour it but will not override the network logic if the calculated date conflicts.

Start-to-Finish (SF) Logic

The rarest dependency type: the successor activity cannot finish until the predecessor has started — almost always a sign of poor schedule modelling.

Start-to-Start (SS) Logic

A dependency type where the successor activity cannot start until the predecessor has started — useful for modelling overlapping or concurrent work.

T

The Iron Triangle (Scope, Time, Cost)

The classical project management model holding that scope, time and cost are interdependent — fixing any two constrains the third, and changing any one forces changes in at least one other.

Three-Point Estimate

An estimating technique that captures optimistic, most likely, and pessimistic values for a cost or duration, rather than committing to a single figure.

Time Impact Analysis (TIA)

A prospective or retrospective delay analysis method that inserts specific delay events into a schedule to assess their impact on planned completion — one of the SCL Protocol's preferred techniques.

Time Risk Allowance (TRA)

Duration added to specific activities in the Accepted Programme to allow for risk — held by the Contractor under NEC4 and distinct from generic float or schedule contingency.

To-Complete Performance Index (TCPI)

A forward-looking EVM metric that calculates the cost efficiency required to complete the remaining work within the budget or forecast.

Total Float

How far an activity can slip before it delays the project end date — with how float ownership works on NEC contracts, and why uniform float across a schedule is a red flag.

Triangular Distribution

A probability distribution defined by minimum, most likely, and maximum values, forming a triangle shape — commonly used for three-point estimates in risk analysis.

V

Variability Risk vs Event Risk

Two distinct categories of risk in QRA: variability is the inherent uncertainty in how long something will take or how much it will cost; event risk is a discrete occurrence that may or may not happen.

Variance at Completion (VAC)

VAC = BAC − EAC: the most direct signal of whether your project will finish within budget. A practitioner guide to reading Variance at Completion, common misreadings, and why the trend matters far more than a single figure.

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Plain-English project controls glossary.

A