Professional Development (PD) is widely accepted as a central feature of any improvement strategy and can perhaps be seen as the very heart of attempts to create a learning culture. Indeed, PD is an important element capable of enhancing what I have referred to as 'system cognition'. If we are to take the learning organization seriously, then professional learning must be central. It is, therefore, conceptualized not as an isolated or individual or external activity but as a collective or collegial process built into the very fabric or 'cognitive system' of the institution.