With the recent approval of enzyme replacement therapy for Pompe disease, insight into the social consequences of this disorder becomes even more relevant. The aim of this study was to measure the impact of late-onset Pompe disease on participation in daily life activities and to evaluate the applicability of the Rotterdam Handicap Scale (RHS) for use in Pompe disease. Two hundred fifty-seven adult patients from different countries participated in the study. The mean RHS score was 25.9+/-6.5 on a scale of 9-36. Individual item scores were lowest for 'domestic tasks indoors', 'domestic tasks outdoors', and 'work/study'. The mean RHS score differed significantly between patients with and without respiratory support (22.9 vs. 28.5, p<0.001) and patients with and without a wheelchair (20.9 vs. 29.5, p<0.001). No differences in RHS score were found between countries. The RHS showed good internal consistency and excellent Test-retest reliability. A ceiling effect of 8% was present. We conclude that the RHS seems suitable for this patient population and that Pompe disease has a large impact on the participation in daily life activities, in particular on the ability of patients to fulfil their work or study.