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In summary, the general qualitative ideas of flux creep theory appear to be soundly based and to allow for the qualitative and semiquantitative understanding of a wide range of phenomena. Many problems remain, both for detailed quantitative study and even for better qualitative understanding. To list a few of these:(1) More detailed understanding of flux line interactions, in particular a sounder basis for the "bundle" concept and an understanding of Bs and of the pea, k eHect.(2) The peculiar transient pulses observed by Kim et at. s These support the creep idea qualitatively, but are too large to be individual lines or bundles and too small to be instabilities. Are they avalanches'(3) The nonlinear diffusion equation: when is it unstable'(4) The viscous state. This is a completely new theoretical problem and I know of no obvious way even of approaching it from fundamental theory.