Two agricultural development projects based on conservation agriculture and agriculture/livestock integration are currently being implemented in Madagascar that takes into account both a "watershed approach" and a "farming system approach" for dissemination of adapted technologies: BV-lac in the area of Lake Alaotra and BVPI-SEHP in Vakinankaratra (Central highlands) and South-East. A farming systems reference monitoring network (FSRMN) has been set up since 2007 with two objectives: i) to help the project in decision making processes for choosing appropriate technologies that will be developed according to a farmer's typology using prospective analysis, ii) to monitor the project's economical impact in the short and medium term. A farming system modelling approach using a software developed by INRA-CIRAD-IAMM ("Olympe", JM Attonaty, INRA), has been developed with project operators in order to cope with the local context and its diversity to promote the best adapted technologies for farmers' conditions including Direct Seeding mulch-based cropping systems conservation tillage (DMC or Conservation Agriculture) and livestock integration. Meantime a new land titling method through "land certification" has been developed since 2003 to secure land tenure. The approach is based on partnership (smallholder, farmers' organizations, project operators and local administration), farming system analysis, and modelling for a Decision Support Systems (DSS) project orientation. This paper presents the methodology, the tools, and some results from the BV-lac project in the lake Alaotra region. FSRMN and farming system modelling (FSM) linked with innovation process assessment tools lead to identification of local innovation processes, adoption and/or adaptation of DMC systems by farmers in order to understand farmers' strategies and to adapt technologies to the farmers' situations and constraints. Adoption of conservation agriculture (CA) represents both a real change of paradigm fo