Complex sentence: The Directory was seen as a valuable source of information for many, including the medical and legal professions, and was the definitive guide for anyone trying to find details of charities in the Bailiwick.
Split into simpler sentences: The Directory was seen as a valuable source of information for many, including the medical and legal professions. In fact, it was the definitive guide for anyone trying to find details of charities in the Bailiwick.