Your role as coach is to guide the leader in designing a developmental plan. You will use data that you and the leader are comfortable with and have gathered from trusted sources. What data is available to you will depend on the situation.
Consider the following data resources.
360 assessments and feedback responses.
Questionnaires and surveys.
Interviews from colleagues, supervisors, and direct reports.
Direct observations and performance data reviews.
Reflect on why you are interested in gathering data for coaching your leader.
Does it provide baseline information?
Are you looking for it to pinpoint specific strengths and needs for development?
Will it be used as a planning tool to help your leader compare where they are with where they want to be?
Can it suggest the kinds of developmental options that would have the greatest impact?
Will it be used as a comparison tool to display growth and progress at the end of the coaching process?
Once data is gathered, you will need to analyze and diagnose the feedback. Look for themes that suggest areas of strength and opportunities for improvement.