Also many studies have dealt with developmental intervention in agriculture, most of them have do not pay attention to the way farmers use such intervention to develop their activity or themselves. The review of existing approaches of farming activity and their translation into developmental approach leads us to propose to renew such approaches by understanding the way farmers mobilize informational resources in order to cope with their situation but also to develop their activity and themselves. We firstly qualify the notion of informational resources, and then display the diversity of livestock farmers’ logics for mobilizing external immaterial resources as it emerges from our inquiry amongst 30 livestock farmers. Based on longitudinal follow-up in 9 farms, we then propose some tracks to understand how farmers link internal and external resources to develop their activity. We draw some perspectives along which this work can be useful to propose new developmental intervention in agriculture.