At some stage during their careers, most Sappers will return to Chatham to continue their professional development. This phase of their training is known as Phase 3. Phase 3 training can be split into 3 main categories: trade training, command and leadership training, and professional engineering.

Trade Training
After an initial 4 years, many Sappers elect to continue their career by extending their period of engagement. As a consequence, most will have the opportunity to further their trade skills and gain additional military, and where appropriate civilian, qualifications. For many this will be achieved in artisan training at Chatham.

Command & Leadership
On promotion to Corporal and Sergeant, Sappers come to undertake their respective Junior Command, Section Commander and RE Senior Non-Commissioned Officer Courses. There they will be provided with the necessary command and supervisory training required to operate effectively in their unit.

Professional Engineering
Professional Engineering Wing delivers advanced technical training to foundation degree standard for selected Junior NCOs in order to deliver force infrastructure, reconstruction and development projects on operations. High quality tradesmen may apply to attend Clerk of Works/Military Plant Foreman courses.