The triple bottom line is a common model of measuring sustainability developed by John Elkington in the 1990s. The model, which had te corporate world as its initial audience, emphasizes the importance and interconnectedness of the three P's: people, planet, and profit. The idea is that companies should measure their sustainability by examining their performance in regard to their support of people's welfare, their impact on the planet, and the economic effects of their decisions. This framework has been adopted in many other institutions, including many higher education institutions. The model has sometimes been reframed as the three Es: ecology, economy, and equity.
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