The main aim of this research was to analyse teachers' views of pupil assessment. The theoretical framework was based on existing literature on advances and challenges of pupil assessment in regard to support for learning, fairness, educational partnership, feedback, and favourable methods. The data were gathered by means of a questionnaire designed for teachers of comprehensive schools. Teachers were first asked to describe a good (right/fair) and a bad (wrong/unfair) case of pupil assessment selected from the period of latest three years. Second, two lists of factors were presented, and respondents were asked to indicate which were the most influential in making pupil assessment either difficult or easy. One hundred twenty-six teachers completed and returned the questionnaire. A descriptive, mainly qualitative approach was used to analyse the data. The majority of positive views concerned the use of different assessment methods, an interactive approach, encouraging feedback, and criteria clarification. Negative views dealt with improper assessment methods, level of stringency, badly implemented assessment, and weak grounds for assessment. Three factors made assessment as difficult: interpretation of fairness, pupils with special needs, and pupils' heterogeneity. On the other hand, versatile assessment methods, curriculum advice, and pupils' good competencies made teachers' assessment work easy.