**3. Conclusions**

This Special Issue presents up to date research on scour following experimental, numerical, and field approaches covering the interaction of the flow and sediment bed around di fferent structures such as bridge piers, monopiles, propellers, turbines, weirs, grade-control structures, and pipelines. The majority of the papers examined the subject from the empirical or experimental approach (64%); the others are founded on the numerical and field approaches, and a review paper. The leading group of papers was that devoted to the pier scour, with five papers or 36%. The review paper summarizes research works to-date relating to bridge foundations, namely piers and abutments, in supercritical flows. The number of papers published in terms of the research methodology or structure type, namely the experimental approach and pier scour, respectively, are representative of the number of papers most commonly found within scour research in archival journals and conference proceedings. Notwithstanding the number of published research works in a particular area, this does not negate the importance of scour research in the other areas and research approaches.

**Author Contributions:** All three writers contributed equally in the preparation and writing of the paper. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Conflicts of Interest:** The authors declare no conflict of interest.
