This volume presents all the published works - spanning more than thirty years - of Julia Bowman Robinson. These papers constitute important contributions to the theory of effectively calculable functions and to its applications. Outstanding among the latter are Robinson's proof of the effective unsolvability of the decision problem for the rational number field (and, consequently of that for the first-order theory of all fields), and her work that provided the central step toward the negative solution of Hilbert's Tenth Problem. These results provide upper bounds for what one can hope to obtain in the way of positive solutions to the decision problem for special classes of fields and for special classes of diophantine equatons, respectively.Besides thematic unity, Robinson's papers are distinguished by their clarity of purpose and accessibility to non-specialists as well as specialists. The volume also includes an extensive biographical memoir on the life and work of Robinson, who will be remembered not only for her distinctive and vital contributions, but also as the first woman to be elected to the mathematical section of the National Academy of Sciences and as the first woman to be President of the American Mathematical Society.