A model of internal principle for integrating past research findings on adult altruism postulates that although individuals' shared beliefs result in significant group effects, there remains a significant portion of variation due to a subject's "factor" or unique internal rule. To examine the influence of both the level (degree or amount) and the salience (obviousness) of need and deservedness on helping scores, 77 college students (16 men and 61 women) responded to vignettes of 32 helping situations, for a total of 2,464 responses. Analyses of results supported the model, and suggest that both factor salience and factor level influence altruism. Some factors, such as recipient gender, may have more or less influence depending upon both factor salience and factor level; although they operate as a single entity, factor salience and level can be manipulated independently to influence decisions to aid. The internal principle model suggests that for optimal predictability the salience as well as the level of each determinant of altruism should be considered in each helping opportunity. (JAC)