This phenomenological research explores the opinions of social studies teacher candidates about self and peer assessment. It is a descriptive study using qualitative data from a sample of 21 teacher candidates. Research data were collected using a semi-structured interview and the researcher's observation notes. The data were analysed using the descriptive content analysis method. The findings showed that self and peer assessment could serve as a powerful learning activity rather than simply an assessment tool. The results also indicated that self and peer assessment support the development of skills, such as self-regulation, critical thinking and decision-making. Teacher candidates reported that self and peer assessment had positive effects, such as recognizing their own shortcomings, learning by sampling from peers' work, constructive contribution to each other's work, comprehension of the skills and criteria that form the basis of assessment, being part of the assessment process, gaining assessment skills, recognizing individual differences and developing critical thinking skills. Self and peer assessment facilitate the development of a learning environment that is more cooperative, participative and appropriate to the educational needs of initial teacher education students in the 21st century.