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Following are some of the major results obtained in the area of Adaptive Data Structures. Have shown how we can adaptively re-organize lists with non-stationary access patterns by utilizing a concept called "lists-on-lists" (Proc. WEA 2006, The Comp. Journal 2007). Devised the conditional rotation heuristic (and other heuristics) for the Ternary Search Tree (Proc. ACMSE 2005, The Comp. Journal 2005). This paper was cited as being Most Meritorious, and was a winner of one of the Wilkes Best Paper Awards in 2006, from the journal The Computer Journal. The Computer Journal is the flagship journal of the British Computer Society. Have generalized the Swap-with-Parent scheme for list reorganization. This was done by viewing the list as a conceptual sequential tree with arbitrary topology, but with no lexicographic ordering. The accessed element is moved to the the parent of this conceptual sequential tree. We have also shown the time reversibility of such generalized schemes. Have presented the Swap-with-Parent scheme for list reorganization. In this scheme the list is viewed as a conceptual complete heap with no lexicographic ordering. The accessed element is moved to the parent of this conceptual heap (Proc. ISAAC 1997). Have also studied the problem of reorganizing a linear list for the case when the elements are requested in sets as opposed to individually (J. App. Prob. 1995). Have proposed new algorithms, which are possibly the only known algorithms of their kind, which dynamically reorganize binary search trees using conditional operations (IEEE T:KDE 1993). Have worked in the area of list organization for the doubly-linked list. Have proposed a new ergodic heuristic - the SWAP Heuristic, and two new absorbing heuristics. Have also proposed the only reported stochastic heuristic (Comp. Journal 1992, J. of Alg. 1993). Have worked in the area of linear list organization for the case when the query distribution is time varying (Proc. ISCIS 1991). Subsequent to the algorithm below, have also discovered the only known algorithm to optimally organize lists using deterministic Move-to-Rear list operations (Th. Comp. Sci. 1990, 1993). Have discovered the only known algorithm to optimally organize lists using stochastic Move-to-Rear list operations (SIAM J. C. 1987).