Evolutionary fitness of traits or behaviors is inclusive [1] of their ‘direct’ effects on the trait bearers’ reproduction and their ‘indirect’ effects on others’ reproduction (Figure 1). Inclusive fitness models lay bare that traits can be selectively advantageous even when they negatively impact direct fitness. A capstone of this approach is that Darwin's dilemma of sterile workers and nonreproductive helpers seems neatly solved by the simplicity of Hamilton's Rule (rb – c > 0). Workers work and helpers help to maximize their inclusive fitness.