Development quango Milton Keynes South Midlands (MKSM) director Hilary Chipping said its plan, signed off last week, "highlights the fundamental interventions needed to achieve growth".
The plan was prepared to guide the area until 2021, the end of a 20-year period during which it is supposed to deliver 224,000 homes and 192,000 jobs.
But it admits: "No part of MKSM consistently met targets between 2001-02 and 2006-07. The likely slowdown over the next few years may compromise plans to ramp up completions."
Only Bedford and north Northamptonshire have core strategies in place. Local plan periods have ended in Aylesbury Vale and west Northamptonshire and alternatives have yet to be adopted.
Aylesbury Vale District Council head of planning John Byrne said: "We were told we could not twin-track our core strategy and allocated sites document and had to start again. We expect the strategy to be agreed next year and adopted in 2010."
The business plan is available at PlanningResource.co.uk/doc