selfappraisal andor the preparation of portfolios may also require considerable time and efforts from school leaders bearing in mind the often heavy workload and range of responsibilities of school leaders this is an important point to consider ginsberg and berry opinions about the effectiveness of portfolios were divided different school principals perceived their work on portfolios either as a compliance tool documenting their past achievements or as a forwardlooking tool for goalsetting and professional development johnston and thomas argued that it was the contextualisation of portfolios in a larger supportive social network of professional practice that enabled portfolios to function as a learning tool they ultimately suggested that considering the time and efforts involved portfolios can mainly serve as a tool for formative appraisal