Waiting times for NHS treatment are at an all-time low, but some areas have been more successful in meeting the challenging targets than others. This research summary outlines recent work from The King's Fund on waiting times for the Department of Health. It looks at the work carried out by three groups of hospitals: those that have sustained reductions, those with variable performance, and those with a poor record. Drawing on interviews with clinicians and managers, it identifies factors that separate successful from unsuccessful NHS trusts. Finally, it makes recommendations for ways forward.