Assessing the dispositions of pre-service teachers who are in field internship experiences has been gaining attention by those persons responsible for the education and training of pre-service teachers. Disposition indicators have already been validated by researchers so that now raters know what to rate. There is an amorphous quality to the validated indicators which suggests a need for clearer descriptions of each indicator so that ratings agreements are enhanced among raters. The purpose of the current study was to expand previous disposition assessment efforts by operationally defining the validated indicators so that the construct represented by each indicator is better understood by raters and ratees. Researchers strived to develop a greater understanding of dispositions being assessed in teacher field education programs by identifying descriptors which clearly focus on the conceptual meaning of a given disposition. Through a search of related literature and a series of interviews conducted by the research team, an instrument with more indicator clarity and description was developed to measure candidate dispositions in the field/clinical experience for teachers in training.