The structure of seed systems has important implications for how likely they are to effectively supply high quality seed to communities of farmers. We evaluated seed system networks defined by a regional potato farmer consortium (CONPAPA) in Tungurahua, Ecuador. Networks were structured around farmer seed and potato transactions and their sources of information about pest and disease management. We performed a scenario analysis of disease spread that takes into account interacting biophysical, socioeconomic and informational elements. CONPAPA provides training, seed improvement and potato processing and marketing for its members. The high centrality of CONPAPA in the network means that disease management interventions, such as training, monitoring and variety dissemination should target CONPAPA staff and processing facilities. The market in Ambato, the largest nearby town, was the next most useful place to monitor. Farmers reported receiving advice about disease and pest management through trusted CONPAPA technical staff. Local agricultural stores were also reported as providing advice to many farmers, but were viewed by farmers as significantly less reliable. Training of store owners could provide one way to improve outcomes in this seed system. Farmer access to information (number and quality of sources) was equal for both genders. Female farmers had a smaller than expected amount of the market share, however. In CONPAPA there is 47% adoption of improved seed, much higher than the 2% rate reported for Ecuador in general. This is probably improving yields significantly for small farmers in the consortium. Agricultural seed systems and network analyses provide one window into a variety of global change phenomena encompassing environmental and societal concerns.