His research has been focused on the search for effective treatment for patients with motor neuron diseases and motor neuropathies by delineating the biological and molecular pathways that initiate and/or drive motor neuron degeneration. These efforts are based on clinical, lifestyle, environmental,genetic and imaging data obtained from large population-based case–control studies. Part of the research activity has been focused on characterizing the phenotype, diagnosis, pathology and treatment options for multifocal motor neuropathy, which is an important treatable ALS mimic. He is principal investigator of the largest, prospective population-based case-control study in ALS (PAN) to provide class I level of evidence of both environmental/lifestyle and genetic factors that determine risk and outcome of ALS and related motor neuron disorders. His research group has strong bioinformatic expertise in genome-wide association studies, copy number variation, gene expression pathways and other systems biology approaches. He is founder and director of The Netherlands ALS Center, which aims to improve the diagnosis, treatment/care and scientific research for ALS in The Netherlands. He promotes international collaborations on ALS research as chairman of the European Network to find the Cure for ALS (ENCALS)) and as coordinator of awarded EU grants (FP7 Euro-MOTOR (systems biology), JPND SOPHIA (biomarkers)).He promotes international collaborations on ALS research as chairman of the European Network for the Cure of ALS (ENCALS)), as coordinator of awarded EU grants (FP7 Euro-MOTOR(systems biology), JPND SOPHIA (biomarkers)) and as initiator of the worldwide ALS genetics research Project MinE.