Summary: In this study, the researchers created a development-oriented evaluation framework, which provides constructive feedback on the personal growth of volunteers. To assess the process by which a volunteer becomes a competent practitioner, a competence taxonomy with five levels of attainment was adopted.

Findings: The competence of volunteers could be measured by the volunteers' attainments in three areas: degree of commitment, acquisition of knowledge, and utilization of skills. A competence-based evaluation framework of volunteer progress ensures that volunteers receive structured and constructive feedback.

Applications: The proposed development-oriented evaluation tool will help keep track of volunteers' progress and encourage the development of personalized strategies according to each volunteer's needs. It will also be informative to the quality improvement of volunteer services.