Diversity is important for any organization, its development and growth. However, frequently we observe that, if left to their own devices, many social and professional communities become self-selective, less susceptible to change, and, thus, less diverse. For example, this phenomenon can be readily observed in the academia when a professor forms a research group that is mostly comprised of people from certain origin or personal qualities. While on an individual level, this situation can be quite convenient and even beneficial, on the large scale the lack of diversity creates severe distortions and discourages many talented individuals from joining the group, organization, or industry in general. Diversity that includes ethnic, age, and gender aspects is a serious concern in overall energy industry and academia. One of the most prominent field impacted by diversity problems is petroleum engineering which can be used as a learning opportunity for other branches of energy industry. Using petroleum engineering community, we can understand what processes have led it to become self-selective, what measures have been applied to changes the situation and introduce more diversity.