It has been widely argued that networks are critical for innovative firms. In the effort to support the growth of these firms, incubators seem to institutionalize support by having systems in place to encourage networking and help firms develop networks with other tenants and potential business allies. However, there is a lack of critical empirical investigation of the different types of networks developed by firms. This paper addresses this issue by systematically examining how firms in incubators develop their networks and what types of networks they might aim to build. The study is based on a survey with firms located at Daresbury Science and Innovation Centre in the UK. The results suggest that incubators often generalize their network support without considering that firms may develop different networks based on their needs. The results also demonstrate that the characteristics of firms do play a role in determining types of network. Science and engineering firms develop networks that differ from those of service and IT firms due to their need to access resources from other innovative firms in incubators, from the Science and Technology Facilities Council and from universities. Similarly, small firms are forced to establish internal and external networks in an attempt to compensate for their lack of resources. Overall, the findings suggest that academic theory on networks of firms in incubators needs to be more nuanced and that the networking support provided by incubators needs to be customized to the actual needs of the incubating firms.