The article deals with selected issues which - as we perceive it - can provide an insight into what the Lakota consider essential and generic for their self-identification with their culture (What does it mean to be Lakota?). The study is based on observations gained during fieldwork research, and issues in the text reflect data collected within this period. As a result, we examine the following issues: tribal museums in Lakota reservations, Native perception of time, selected issues of Lakota religion, and Lakota relation to the land and environment they live in and to the world on a global scale. We believe that in all these issues we can also recognize an underlying dual structure which - in its most general meaning - could be understood as a dichotomy of Native and Western/Euro-American worldview and mind-set. The question was how non-Native elements distort or affect the system of Lakota culture. In the section on tribal museums and perception of time we have shown that circular way of thinking about the course of the world which is, according to Donald Fixico (FIXICO 2009), characteristic of all Native cultures affects the way tribal museums organize and present their exhibitions. In this case, the influence of the Native/Euro-American dualism does not have to be necessarily negative. The same can be said about another example where the dichotomy projects itself - in the issue of Lakota relation to the land or Unci Maka (Grandmother Earth): Though Lakota religion and identity is regionally bound (BUCKO 2008), their concern for this integral part of their Native-self can surprisingly well fit into the global issue of protection of environment. On the case of Lakota struggle to stop construction of a KXL pipeline1 we demonstrate how the same (Native/Euro-American) duality interacts and through which the Lakota (Native, regionallybound) voice is strengthened by its non-Native counterpart and vice versa.