Evidence on voluntary sustainability standards effectiveness and impact is strengthening, but little evidence exists on the efficacy of growing numbers of Responsible Business Initiatives (RBIs) which focus on entire corporate sustainability. Some are mature (e.g. corporate codes), others are more recent (e.g. sectoral multi-stakeholder initiatives, supplier capacity strengthening approaches, benchmarking initiatives, mobilizing investors). But quality evidence and rigorous synthesis is generally very thin across the board.
