The extent to which conversion to organic farming influenced habitat diversity within Less Favoured Areas (LFAs) was determined. Similar numbers of conventional (not converted) (n=16), recent converts (<5 years; n=13) and long-standing converts (>5 years; n=16) were surveyed. Each holding was characterised in terms of habitat classes using a rapid ground survey. Conversion to organic farming had little effect on overall habitat diversity. This could be linked to the physical challenges of farming in LFAs limiting management options. The results highlight the need for a separate evidence base for the development of policies relating to farming and biodiversity in marginal areas.