 While many of Dedekind’s contributions to mathematics and its foundations are thus common knowledge, they are seldom discussed together. In particular, his foundational writings are often treated separately from his other writings. This entry provides a broader and more integrative survey. The main focus will be on Dedekind’s foundational writings, but they will be related to his mathematical work as a whole. Indeed, it will be argued that foundational concerns are at play throughout, so that any attempt to distinguish sharply between his “mathematical” and his “foundational” work is artificial and misleading. Another goal of the entry is to establish the continuing relevance of his contributions to the philosophy of mathematics. Their full significance has only started to be recognized, as should become evident. This is especially so with respect to methodological and epistemological aspects of Dedekind’s approach, which ground the logical and metaphysical views that emerge in his writings.