The report shows the results from the characterization of the biophysical and socioeconomical dimensions of diary milk herds, from Mesa de los Santos, Santander. The goal of this work is to promote a design of baseline instrument for protocol of Best Management Practices. The process of the comprehensive characterization of the production systems were focused on participatory methodologies and Action Research. Were identified and described two producer groups, the first characterized by very good economic condition. They incorporate technological elements. The production infrastructure was oversized, especially in capital investment, not related to the inefficiency of production processes. The second group of smallholder rural economy, rural people who run a small cattle inventory supplemented by agricultural activities, but focused on milk production.