Human rights and equality for lesbian,gay, bisexual, and transgender (LGBT) people are usuallyconsidered through a social, cultural, or ethical lens, butequality and inclusion of LGBT people are also economicdevelopment issues. This report develops a model to estimatethe economic cost of stigma; negative attitudes toward LGBTpeople and the exclusion of LGBT people in socialinstitutions such as education, employment, families, andhealth care. The model is applied to a case study of India.Three major findings emerge from this report. First, thereis clear evidence of stigma and exclusion exists for LGBTpeople in India. Data on public opinion from 2006 shows that41 percent of Indians would not want a homosexual neighbor,and 64 percent believe that homosexuality is neverjustified. Negative attitudes have diminished over time,however. Second, the effects of stigma and exclusion arepotentially costly to economies. A conceptual model linksexclusion of LGBT people and economic development through(1) lower productivity and lower output as a result ofemployment discrimination and constraints on labor supply;(2) inefficient investment in human capital because of lowerreturns to education and discrimination in educationalsettings; (3) lost output as a result of health disparitiesthat are linked to exclusion; and (4) social and healthservices required to address the effects of exclusion thatmight be better spent elsewhere. Third and lastly, in India,existing research does not allow for a precise estimate ofthe cost of LGBT exclusion, but the cost could besubstantial. The loss of labor productivity and outputbecause of employment discrimination and the loss of lifeyears due to early death or disability will reduce theeconomic output of the Indian economy. With better researchon the lived experiences of LGBT people, researchers coulduse existing analytical tools to estimate the total cost ofLGBT exclusion.