The relationships between faith affiliation, religiosity, and altruistic behaviors remain debated in the literature. As a recent example of such debates, Decety et al. (2015) published an article suggesting that children from Christian and Muslim households may be less altruistic than children from non-religious homes. Using experimental data collected from 1,151 children between the ages of five and 12 attending schools in Amman (Jordan), Cape Town (South Africa), Chicago (United States), Guangzhou (China), Istanbul and Izmir (Turkey), and Toronto (Canada), Decety et al. concluded that (1) Children in families that identify as religious had on average less altruistic behaviors; (2) Family religiousness was associated with parents self-reporting that their children were more sensitive to injustices and had empathy towards others; but in the experiment (3) Children from religious households were actually harsher in their punitive tendencies. These results were however challenged in a subsequent communication published by Shariff et al. (2016) in the same journal. When controls were included in the regression analysis for crosscountry variations in altruistic behavior, the results pertaining to the effect of religion and religiosity did not hold anymore. Apart from being a cautionary tale about how empirical results may be sensitive to the specification used by authors, this episode suggests that even though much of the literature seems to point to a positive relationship between religiosity and altruistic behaviors (see for example Wodon 2015, in the case of faith-based service delivery in education and health in Africa), there is no universal consensus on the matter, and the matter is complex. The literature is complex in part because the factors leading to altruistic behaviors are themselves complex, calling for a variety of approaches and data to explore those relationships. Evidence on the relationship between religiosity and altruistic behaviors can be collected in many different ways. The paper by Decety et al. (2015) and the comment by Shariff et al. (2016) relied on experimental data. These analyses remain the exception rather than the rule, with much of the literature still based on non-experimental data despite the limits of such datasets (Sablosky 2014). In general, as already mentioned, the literature seems to suggest that religiosity is often associated with altruistic behaviors. Examples based on data from the United States help illustrate this finding. Forbes and Zampelli (2014) find that greater intensity of religious belief is associated with more volunteerism. Kim et al. (2016) look at how trajectories of religious attendance relate to volunteering over a 15-year period. They find a positive association between rates of change in religious attendance and volunteering, as well as higher increases in volunteering over time for individuals with higher initial levels of religious attendance. Another interesting paper by Hill and den Dulk (2013) considers how the type of secondary school attended may ...