My paper is devoted to scientific passion and its connections with scientific effectiveness. Following some preliminary considerations concerning a context of my paper. I come to description of mechanisms determining a level of engagement into scientific activities. Next part of the paper is concerned with environmental determinants of engagements into scientific work. In contemporary attitude toward creativity (including scientific one) a notion of passion is used seldom, if at all. It's connected with motives and emotions in creative process, and its research isn't dominant in present-day psychology. So, one of the aim of my paper is to try to incorporate the notion of passion into the perspective of up-to-date approach to scientific creativity.