The nature of the business that a listed company operates defines a socially-responsible investment. The two major strands of socially responsible investments include the avoidance of investment (thus a negative selection strategy) in stocks that produce or sell addictive substances (like alcohol, gambling and tobacco) and seeking out stocks (thus a positive selection strategy) engaged in social justice, environmental sustainability and alternative energy/clean technology efforts. Individual stocks, a socially-conscious mutual fund or exchange-traded fund (ETF) are ways of obtaining SRI exposure.