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Conservation agriculture, based on the combined implementation of (i) minimal soil disturbance, (ii) soil cover by crop residue retention or cover crops and (iii) crop diversification, has been identified as a sustainable improvement of conventional agriculture practices. It can decrease soil degradation and erosion, improve water conservation, enhance soil life, improve labour efficiency and decrease fossil fuel dependence. Despite these benefits, adoption of conservation agriculture among smallholder farmers has remained limited. The International Maize and Wheat Improvement Centre (CIMMYT) is investigating and disseminating conservation agriculture practices under small and medium scale maize based production systems in Mexico. In this research, eight experimental platforms were examined to evaluate the sustainability of conservation and conventional agriculture practices, based on the evaluation of the diagnostic criteria (i) soil quality, (ii) yield and (iii) profitability. The platforms are linked to CIMMYT’s conservation agriculture program and located in central and south Mexico. Physical soil parameters that were assessed are indicative for direct infiltration, aggregate distribution and stability and soil resistance to penetration. Chemical soil quality was evaluated based on the assessment of the soil pH, C/N ratio and soil organic C content. At the long-term experiment an in depth focus on plant available P was carried out, using the DGT method, that mimics diffusion processes at plant root level. Yield and profitability were determined. Zero tillage plots with crop residue retention resulted in the best infiltration. Aggregate distribution and stability did mostly improve under zero tillage with residue retention, although no positive effects of this treatment were observed at the two driest locations. Tillage with residue removal resulted in the easiest penetrable topsoil, while zero tillage with residue retention created in most platforms a topsoil with a higher resistance to penetration. At deeper layers (30-60 cm) this trend was reversed. Most significant treatment effects on the soil chemical characteristics were observed in the topsoil (0-5 cm) where both the C/N ratio and soil organic C content tended to increase under zero tillage with crop residue retention. A significant treatment effect on plant available P was observed while conclusions on the most P beneficial treatment are yet to be drawn. No treatment effect on yield and profitability was observed. The overall results indicate a net positive effect of conservation agriculture on the sustainability levels of the assessed parameters. However, not all benefits of conservation agriculture can be generalized across all assessed locations. This emphasizes the importance of continued field research on how best to adapt the general principles to local circumstances in order to increase adoption of conservation agriculture.