Editorial: Attention-deficit/hyperactivity disorder: a continuing challenge to researchers, practitioners and carers

This editorial introduces a collection of research papers and a review on ADHD, highlighting the continuing challenge that ADHD poses in research and practice. The articles include a Practitioner Review providing a comprehensive review focusing on current knowledge about barriers and facilitators operating at the individual, organisational and societal level; a study reporting a randomised controlled trial of parent training for ADHD pre-schoolers; an empirical paper on sex differences in ADHD symptom severity; a study of the co-development of ADHD and externalizing behaviour across the lifespan; a study of the genetic architecture of neurocognitive abilities in the general population; and finally a study examining the differential association among three behavioural dimensions leading to early-onset conduct problems.