Experimental perspectives on heavy-electron metals.

We motivate the description of heavy-electron metals in terms of concepts from the Kondo problem. These concepts are used to discuss magnetism and superconductivity in heavy-electron systems. Particular attention is given to what we view as the principal outstanding questions in this field and directions in which the field is developing. This will include consideration of the differences between Ce and U heavy-electron compounds as well as the occurrence of very small ordered magnetic moments.