This systematic review evaluates the efficacy of nonpharmacological therapies (NPTs) in Alzheimer's disease (AD) and related disorders (ADRD). The study analyzed 179 randomized controlled trials (RCTs) and found that multicomponent interventions for caregivers (CGs) significantly delayed institutionalization of individuals with mild to moderately severe AD. These interventions included individual assessment, information, counseling, and support, with sessions lasting 30–90 minutes every 2 months. After 6 or 12 months, the institutionalization rate was 10.6% in the intervention group versus 14.9% in the control group. A 11-year intervention showed a 557-day delay in nursing home placement. Cognitive training and cognitive stimulation improved specific cognitive skills, with positive results in memory and learning. Cognitive stimulation also improved attention, memory, orientation, language, and general cognition. When combined with other components, such as relaxation, it enhanced general cognition. In a high-quality RCT, cognitive stimulation combined with donepezil improved cognitive function. ADL training improved performance in nursing home residents with cognitive impairments. Group sessions of cognitive stimulation, reminiscence, and relaxation improved orientation after 3 months, while usual care led to deterioration. Cognitive stimulation plus psychomotor exercises reduced deterioration in instrumental ADLs. Multicomponent interventions for PWDs and CGs improved mood, with a progressive improvement in affective symptoms after 1 year. A 6-month program of physical exercise and behavioral management improved mood, with significant results after 3 months. Multicomponent interventions for CGs improved CG mood, with education and support programs reducing stress and improving mood. CG education for coping skills was particularly effective for those with psychological morbidity. CG support and electronic devices improved CG mood after 6–12 months of use. Multicomponent interventions for CGs improved CG psychological well-being and quality of life. A high-quality RCT showed improvement in CG quality of life after 6 months. Professional CG training for alternatives to restraint reduced mechanical restraint in institutionalized PWDs, with no differences in falls, mobility, or use of psychotropic drugs between experimental and control groups. The review found that NPTs are cost-effective and can be used to improve outcomes and quality of life for both PWDs and CGs. They are often low-cost and have minimal side effects, making them preferable for targeted ADLs or behaviors. NPTs should be viewed as complementary to drugs rather than alternatives. However, the study highlights the need for more high-quality RCTs, particularly in areas like reminiscence, music, and physical exercise. Future research should focus on response mediators and improve study design to better evaluate NPTs.This systematic review evaluates the efficacy of nonpharmacological therapies (NPTs) in Alzheimer's disease (AD) and related disorders (ADRD). The study analyzed 179 randomized controlled trials (RCTs) and found that multicomponent interventions for caregivers (CGs) significantly delayed institutionalization of individuals with mild to moderately severe AD. These interventions included individual assessment, information, counseling, and support, with sessions lasting 30–90 minutes every 2 months. After 6 or 12 months, the institutionalization rate was 10.6% in the intervention group versus 14.9% in the control group. A 11-year intervention showed a 557-day delay in nursing home placement. Cognitive training and cognitive stimulation improved specific cognitive skills, with positive results in memory and learning. Cognitive stimulation also improved attention, memory, orientation, language, and general cognition. When combined with other components, such as relaxation, it enhanced general cognition. In a high-quality RCT, cognitive stimulation combined with donepezil improved cognitive function. ADL training improved performance in nursing home residents with cognitive impairments. Group sessions of cognitive stimulation, reminiscence, and relaxation improved orientation after 3 months, while usual care led to deterioration. Cognitive stimulation plus psychomotor exercises reduced deterioration in instrumental ADLs. Multicomponent interventions for PWDs and CGs improved mood, with a progressive improvement in affective symptoms after 1 year. A 6-month program of physical exercise and behavioral management improved mood, with significant results after 3 months. Multicomponent interventions for CGs improved CG mood, with education and support programs reducing stress and improving mood. CG education for coping skills was particularly effective for those with psychological morbidity. CG support and electronic devices improved CG mood after 6–12 months of use. Multicomponent interventions for CGs improved CG psychological well-being and quality of life. A high-quality RCT showed improvement in CG quality of life after 6 months. Professional CG training for alternatives to restraint reduced mechanical restraint in institutionalized PWDs, with no differences in falls, mobility, or use of psychotropic drugs between experimental and control groups. The review found that NPTs are cost-effective and can be used to improve outcomes and quality of life for both PWDs and CGs. They are often low-cost and have minimal side effects, making them preferable for targeted ADLs or behaviors. NPTs should be viewed as complementary to drugs rather than alternatives. However, the study highlights the need for more high-quality RCTs, particularly in areas like reminiscence, music, and physical exercise. Future research should focus on response mediators and improve study design to better evaluate NPTs.