In one way or another—and often in various ways—all the contributors are indebted to Barry Smith. Some of us were Smith's students, and took our first steps in academia in the context of collaborative work with him. But even those who have never been, technically speaking, Smith's students, have nonetheless immensely benefited from his penetrating intelligence. As a matter of fact, in connection to Smith, the categories of 'student", "colleague", and "collaborator", exhibit remarkable overlaps. All the contributors are equally grateful to Barry and they dedicate this volume to him, in friendship and in admiration indeed.