A program to develop a new fuel element was initiated at Hanford in 1951. A survey of the possible methods of making such a fuel element was completed and a document listing all possible lines of research was written. The problem was outlined as it appeared at that time; various developments which have occurred subsequently have changed this problem to a greater or lesser extent. Essentially the problem concerned the development of a fuel element which would not fail or would fail in a slow and predictable manner and would not cause damage to the pile. A largenportion of the research and development was concerned with the application of these layers. This paper will review the research that was done on the development of these corrosion-resistant layers and will evaluate the problem as it appears now after approximately four years have elapsed.