Objectives To explore patients' and carers' views on what constitutes high-quality communication and information provision during diagnostic assessment in memory clinic services in three areas of England. Methods Interviews with 27 people with cognitive impairment (13 with confirmed dementia) and 26 carers (20 matched pairs). Interviews continued until theoretical saturation was reached. Interview transcripts were subject to constant comparative analysis; data interpretation occurred in ‘data clinics’. Results People with memory problems undergoing assessment often have unmet information needs, especially patients with a diagnosis other than Alzheimer's disease and those who do not receive a diagnosis. Patients wish to be kept informed about both the assessment and its outcomes. Some have unrealistic expectations of the process (expecting assessment and diagnosis to be complete in two weeks) and some experience what appear to be long delays (over 12 months) in receiving results. Most appreciated clear and honest communication about any diagnosis. Post-diagnostic groups, organized by local memory services, afford opportunities to learn practical strategies and gain informal peer support. Voluntary organizations may be an essential source of information. Conclusions Communication and information need improvement for patients undergoing assessment for possible dementia, especially for those considered unlikely to benefit from medication and those with mild cognitive impairment.