In many developing countries, sanitation and hygiene still come low down in political and policy priorities. In many central ministries and regional/district agencies, budget holders are not yet convinced of the benefits of investment in sanitation and related hygiene (and water) interventions. ODI, Tearfund and the Water Supply and Sanitation Collaborative Council (WSSCC) have gathered views from sanitation and hygiene (‘S&H’) specialists and health practitioners to review progress in advocacy for S&H to the health sector, as a prime target for the promotion of S&H services. This Background Note summarises the perceptions of both S&H and health specialists on the opportunities for, and obstacles to, greater collaboration between the two sectors, and the need to build capacity as part of the long-term solution.