Purpose: To identify and understand factors influencing farmers' decisions to engage with extension activities. To understand farmer segments and how these factors vary in order to develop recommendations for future extension delivery. Methodology: Qualitative data was obtained through semi-structured interviews with 30 Tasmanian dairy farmers. The Theory of Planned Behaviour (TPB) framework was used to identify and explore factors influencing farmer engagement intentions and behaviour. Findings: There was a negative effect of social influence on experienced farmers' intention to re-engage with extension, due to the belief extension activities were targeted to less experienced, younger farmers. Perceived control factors limiting engagement included lack of confidence about existing knowledge, resulting in farmers perceiving extension activities as confronting.Practical implications: Key factors influencing intention to engage and continued engagement with extension were identified. These findings will inform future design and targeting of extension activities to improve initial and continued engagement. Subsequent recommendations are presented. Theoretical implications: Previous TPB studies on adoption as an outcome of extension have typically focused on quantifying adoption predictions, rather than exploring how social factors interact and influence intentions and behaviours. This paper demonstrates how the TPB can be qualitatively applied to better understand farmer decision making, in this instance with respect to their initial and continued engagement with extension. Originality/value: This paper demonstrates how the TPB can provide an evidence-based framework to qualitatively explore farmer intentions and behaviour. This approach has led to new insights into farmer decision making that will inform improvements in future extension development.