Realizing the importance of colleague communication to the physician's medical knowledge, this study attempted to determine what variables affect the success of local colleague networks in raising the individual physician's information level. In an interview of 400 general practitioners and internists in 15 counties in three states, the questions tested the physician's level of information and awareness of current developments in medicine. Complex relationships were observed between physicians and local networks, with different community structures requiring different ways of attaching to the local network in order to maximize the learning payoff. The appendix describes in detail the interviewing and sampling instruments and techniques, and the information test used. (BH)