Professional development for the further education sector (FE) in England, whether commissioned by the Education and Training Foundation (ETF), or the Department for Education (DfE), is typically formal learning. There are usually measurable outcomes, and practitioners are asked to identify changes to their practice. The focus on outcomes means informal learning is rarely directly funded. This paper analyses a professional development programme funded by the DfE and cut short. This programme was based on a network model that is neither fully formal nor informal. We argue the model sits in a 'grey zone' between formal and informal professional development, and that the specific benefits of this kind of 'grey zone' model should be considered for future commissioned professional development. We find that informal learning in the semi-structured setting created by the Network had the potential to empower and recognise frontline teaching staff, by providing opportunities to present good practices and learn from other Network members. The Network structure enabled responsiveness to practitioners' needs, by being flexible and adapting to circumstances. However, these adaptations made the Network vulnerable to challenge, and this, alongside concerns about the quality of presentations, and a lack of centralised control, ultimately contributed to its downfall. In conclusion, whilst there are undoubtedly risks from a funder perspective of operating in the 'grey zone' these should be balanced against the potential significant benefits to participants of a network approach to professional development.