The aim of the Review of Employer Collective Measures study is to identify credible research from across the four countries of the UK, and other applicable international evidence, to shed light on how the level, nature and quality of training may be improved. The study comprises several separate reviews. The conceptual review outlines the economic theory relating to sub-optimal investments in training, and the policy review looks at the evaluative evidence in relation to those measures which might increase the take-up of training. The reviews are intended to advise which policy levers might most effectively increase employer investment, direct or indirect, in training. This report, the empirical review, sits between the conceptual and policy reviews. It provides evidence of: (i) the extent of employers’ investments in training; (ii) the factors which persuade employers to train; and (iii) the barriers to training faced by employers.