In this essay, I maintain that although atheism, minimally construed, consists simply of the belief that there is no God or gods, atheists must embrace a secular worldview of one kind or another. Since they cannot be without a worldview, atheists must develop an alternative to the religious, especially the theistic, worldviews which they, by implication, reject. Further, I argue that there are, at the very least, two options available to atheists and that these should not be conflated or treated as one and the same. The two options that I explore and distinguish are scientism and secular humanism. I also maintain that the things that might count as good grounds for or against secular or religious worldviews are shaped significantly by whether atheists embrace scientism or secular humanism.