There are at least three distinct sets of roles that must be fulfilled when designing intervention change strategy. The change manager oversees the design of an intervention strategy. This person has overall responsibility for assessing the need for change, implementing a strategy, and evaluating the results. A change agent assists the change manager and has primary responsibility for facilitating all of the activities surrounding the design and implementation of a strategy.

The roles of individuals within a system that is the target of an intervention strategy are determined by the change manager. The system can be a small work group or an entire organization. To design an intervention strategy, the change manager must be able to diagnose the existing environment, develop and implement a plan of action, and evaluate the results of the intervention. Diagnosing the environment is an assessment process that focuses on determining the readiness of a target group to accept change.

Developing an action plan involves identifying specific target variables and determining the techniques that will be used to bring about change. The action plan specifies the intervention strategy. Like any other plan, the action plan should specify the objective of each change activity, who will be involved, who is responsible, and when the activity will be completed. The role of the change manager, with the assistance of the change agent, is to oversee the implementation of the plan and ensure that all steps are followed, that tasks are completed, and that deadlines are met.

The change manager should continually confer with the members of the system to review results, get feedback, and make the appropriate adjustments. HRD practitioners can serve as change agents or as the evaluator of intervention strategies.