Internal decoration is generally quite straightforward and it is less likely to cause problems than outside painting. Modern paints offer a wide choice of finishes and the techniques needed to get a good finish are well known. But there can be snags: you can, for instance, be faced with painting on damp or unsound plaster or dealing with persistent mould growth on walls. Sometimes there are health hazards involved in removing old finishes or applying solvent-based paints indoors. This Good Repair Guide gives advice from BRE on how to tackle some of the problems that crop up during internal painting, where to use fungicidal paints, and when to take safety precautions.