Field experiences aim at immersing student teachers in authentic work tasks and conditions of teachers. However, specific psychological needs of the teaching workforce are not considered when studying the fulfilment of student teachers' psychological needs. This paper proposes a four-dimensional theoretical framework incorporating both basic and specific psychological needs. A diary study is presented, which measures the fulfilment of the hypothesised needs at five intervals during a ten-day field experience. The average fulfilment rates and development trends show differences among the four dimensions, suggesting the presence of lower- and higher-order needs. Significant correlations between need fulfilment and success indicators, such as learner satisfaction, learning gain, teacher self-efficacy and level of self-reflection, are also found. The results highlight the relevance of high rates of need fulfilment right from the start of the field experience.