39 Engineer Regiment provides engineer support to both the Royal Air Force (RAF) and to United Kingdom Land Forces.  One of only 2 regular Air Support regiments in the British Army it is particularly "construction centric" and has a considerable construction capability.  Consequently it is regularly called upon to support UK operational commitments.

The Regiment was joined in Waterbeach on 22 October 2007 by 25 Engineer Regiment, which also operates in the air support role. 34 and 53 Field Squadrons (Air Support) were transferred from 39 Engineer Regiment.

The Regimental ORBAT currently includes:

• 10 Field Squadron (Air Support).
• 48 Field Squadrons (Air Support).
• 60 Headquarters and Support Squadron (Air Support).
• REME Workshop. 

The Regiment shares Waterbeach Station with 12 Engineer Group (Air Support), which commands 25 and 39 Engineer Regiments, and those Territorial Army units which are also committed to the Air Support role.