The number of older adults with Alzheimer's disease (AD) and related forms of dementia is increasing in Canada and the majority of individuals with dementia develop neuropsychiatric symptoms (NPS) such as agitation, psychosis, depression and anxiety at some time during their illness. NPS are particularly problematic in long-term care (LTC) where approximately 60% of individuals have dementia, and 80% of individuals with dementia have NPS at any time. Adverse outcomes associated with NPS include increased use of psychotropic medications, stress for families and nursing staff, increased costs of care, and decreased quality of life. A novel approach to implementing non-pharmacological interventions for LTC residents with NPS is the use of volunteers. Volunteer-led programs have been demonstrated to be an effective, inexpensive, and sustainable method of implementing psychosocial interventions for older adults in acute care. The objectives of our project are to: 1.) Recruit and train approximately 40 volunteers in the VALID program; 2.) Conduct a cluster-randomized controlled trial of the VALID program in 6 LTC facilities (3 intervention and 3 control LTC sites; 60 individuals with dementia in each of the experimental and control arms) to determine the effect of the VALID program on symptoms of NPS, patient quality of life, volunteer's experience, and LTC staff stress, 3.) Determine key components of the VALID program that served as facilitators and barriers to implementation.