Project executives often ask PROMA which framework to standardise on. The honest answer is that IPMA, PMBOK and PRINCE2 are not mutually exclusive — they answer different questions, and a mature project environment usually draws on more than one.
PRINCE2 — process and control
PRINCE2 is strongest where a project needs clear stage boundaries, defined roles, and tight control over what gets escalated to a project board. It suits environments with strict governance requirements — public-sector and capital-projects organisations in particular — where auditability of decisions matters as much as delivery speed.
PMBOK — a knowledge base, not a method
PMBOK is a body of knowledge across ten process areas rather than a prescriptive method. It is useful as a common vocabulary and as the basis for individual PM certification (PMP), but it does not, on its own, tell an organisation how to govern a portfolio.
IPMA — competence of the people running delivery
IPMA's four-level certification (A through D) focuses on individual and organisational competence rather than process. It is the most useful of the three for assessing whether the people in project roles are actually equipped for the level of project they are running.
PROMA's position
PROMA PMIS does not force a single framework onto an organisation. The maturity assessment measures current practice against all three, and the resulting governance structure borrows whichever elements fit the organisation's risk profile — PRINCE2-style stage gates, PMBOK process discipline, and IPMA-informed role competence requirements. The goal is a defensible, audit-ready method your organisation can own, not brand loyalty to one standards body.