Dynamics NAV

Dynamics NAV (originally Navision) was Microsoft's on-premise ERP product for small and mid-sized businesses. It was acquired by Microsoft in 2002 and went through annual releases up to NAV 2018 before being rebranded and re-engineered as Dynamics 365 Business Central. NAV introduced the C/AL programming language and the role-tailored client, and it built a large global partner ecosystem around vertical add-ons. Mainstream support for NAV ended for older versions but many organisations still run NAV 2016, 2017, or 2018 and migrate to Business Central as upgrade projects.

In practice, a NAV-to-Business-Central migration is a re-platforming project, not a simple version upgrade: the underlying data model and posting logic carried over closely, but the C/AL customisation layer did not — C/AL extensions have to be rewritten in AL, the SaaS-native extension language, since C/AL itself cannot run on Business Central Online. Organisations with heavily customised NAV environments (deep code modifications rather than isolated add-ons) typically find the AL rewrite is the largest single line item in the migration budget, which is why a fit-gap assessment of the existing customisation layer is the first real step in any NAV migration, well before data mapping begins.

Where teams get confused: "NAV" and "Business Central" are sometimes used loosely as if interchangeable, but they diverge sharply once extensibility, licensing, and deployment model (on-premise perpetual licence versus SaaS subscription) are considered. A partner who only knows NAV's C/AL customisation patterns is not automatically ready to build extensions the AL way — the two are related but genuinely different development models.