This study examines how primary school teachers view peer assessment. Six teachers were interviewed by semi-structured interviews about how they work with peer assessment with pupils in primary school, how they introduce it and what pros and cons they find with this method of giving feedback. The interviews were summarized with the analytical method called meaning concentration. We used Vygotsky's theory about the zone of proximal development (ZPD) which represents the space between what a learner is capable of doing with a little help called scaffolding from another child. The result was compared to this theory from a sociocultural perspective in the analytical part. The result showed that three teachers used peer assessment as a routine in their class in different subjects, two teachers had used peer assessment earlier but didn’t practice it by the time we had the interviews. One teacher had not used peer assessment with pupils but insisted on potentially using it in the future. The benefit that the teachers saw with peer assessment was that the teachers could focus on the students that needed their help while the other students were used as learning resources to each other. Another benefit was that the pupils developed in their own learning by giving feedback to others, which also prepared them for the peer assessment they would meet in high school. The disadvantage was that it was time-consuming since it required a lot of training before letting the pupils work on their own. One more potential risk with peer assessment was that the quality of the feedback could vary a lot depending on the pupil’s skills of giving feedback. Receiving low quality constructive criticism could make some students feel discouraged to present their work again in this way. The teachers also gave some advice for how to introduce peer assessment in primary school. The conclusions of this study are that peer assessment in primary school requires a lot of time for training as well as the teacher being a role model for the class in order to avoid unwanted conflicts and discouraged students. It is also a good way to prepare the pupils for their future studies and help them develop their own skills in learning.