Bulk operations on data structures are widely used both on user-level but also on programming language level. Iterations are a good example of such bulk operations. In the sequential setting iterations are easy to design on top of an algorithmic construction of a data structure and is not considered as a challenge. In a concurrent environment, such as a multicore system, the situation is completely different and the issue of extending concurrent data structure designs to support iteration operations opens new research challenges in concurrent algorithmic data structure implementations, with respect to consistency and efficiency. In this paper we take a journey through this young and evolving research topic. More precisely we describe recent advances in the area together with an overview of iteration implementations that have appeared in the research literature as well as in widely-used programming environments and we outline a range of application targets and challenging future directions.