The TDA Model outlines a 5 step process for establishing continuing professional development (CPD) needs: 1) identify needs through external factors, school self-evaluation, and performance/development reviews; 2) create an annual CPD plan to address needs; 3) arrange appropriate CPD activities; 4) evaluate the impact of CPD on staff and pupils; 5) draft an annual report evaluating the success of the CPD strategy and implications for the next year's plan, repeating the cycle.