Examines government advice on sustainability appraisal presented to planning authorities in the last few years, driven by the planning reforms in England and Wales and the European Strategic Environmental Assessment Directive (Directive 2001/42/EC). Assesses key changes in the ODPM interim advice (April 2005), which sets out the five principal stages in the sustainability appraisal process and proposes a single scoping report. Highlights two areas of uncertainty in the interim advice: the initial sustainability appraisal report is no longer required despite reference to it in "Planning Policy Statement 12: local development frameworks" and an implied radical re-arrangement of stages B and C of the sustainability appraisal process. Comments on the partial clarification of the differences between supplementary planning and development plan documents. Hopes that the final version of the appraisal guidance will present a clear and feasible process for hard-pressed local planning authorities. Notes.