The UK Department for International Development (DFID) has published a study by Lori Heise: "What works to prevent partner violence?" - click on the title to download it. It is a hefty document - don't be discouraged if you can't find time, just read the short and clear executive summary!
The study draws on evidence from all kinds of places, but it is meant to inform chiefly work in low and middle-income countries. It concludes that the following types of interventions work best to prevent partner violence: