The Field Study reports on the research and development of a Health Assessment Program (HAP) for secondary school students over a period of three years in the ACT. The 'original' HAP is described, and its early implementation methods discussed. Changes are proposed and trialled, and further refinements made, then trialled again. Through this process a new HAP is developed. The 'Research and Development Cycle' (Borg and Gall 1983) provides the theoretical framework for the planning of the field study. (See 1.4). The 'new' HAP exhibits the characteristics of an 'education' program. The physical components have been developed to enable them to be administered by the teachers who are responsible for the organisation of the HAP in their school, and health professionals are only used for those components which require confidential counselling. This is in contrast to the 'original' HAP which was organised and conducted by health professionals. The process by which the changes took place has determined the quality of the new HAP. The developments have been based on the views of the teachers who used the HAP, the students who were tested, and the health professionals who participated. The literature has also been used to provide the direction for, and nature of, the changes. This process has ensured a program which is highly suitable for use in the school environment. It is not envisaged that the HAP has reached its final stage of development. Each school who uses the program is encouraged to modify and adapt it to suit the needs of their own teachers and students.