Interview discusses Allan Sandage's parental background; early interest in science and experience looking through a friend's telescope in the fourth grade; feeling of compulsion as a child to go into science; sense of duty inherited from parents; early reading in science; pleasure of solving problems in science; education at Miami University and influential teachers there; experience in the Navy in 1944 and 1945; education at University of Illinois; learning observational techniques from Robert Baker; getting into the California Institute of Technology (Caltech); the mystery of science; Ph.D. work with Baade on finding and fitting main sequences in globular clusters; history of motives of work with Martin Schwarzschild on dating globular clusters; apprenticeship with Hubble on the 200-inch telescope; Sandage's later monopoly of the 200-inch after Hubble died; Sandage's feeling of responsibility to carry on Hubble's work; objections to the steady state model; learning about the big bang model; limits of Hubble's understanding of the big bang model; influence of theoretical papers by Mattig; influence of Fred Hoyle; introduction to and early attitude toward the horizon and flatness problems; change in cosmology from finding out what galaxies are like to how galaxies originated; Sandage's change in attitude toward the horizon problem; attitude toward the grand unified theories; Sandage's gradual appreciation for the "new" cosmology, involving particle physics; change in attitude toward the flatness problem; attitude toward dark matter and missing mass; openess to the value of omega; problem of consistent ages in cosmology; many forms of evidence for the big bang model; reaction to de Lapparent, Geller, and Huchra's work on large-scale inhomogeneities and importance of similar work done earlier by Gregory, Thompson, Rood, Chincarini and Tifft; relation between theory and observation; science is not the discovery of absolute truth but only an approximation to reality; lack of good observations at the frontiers of science; the change in cosmology from asking only "where" and "what" to also asking "how;" outstanding problems in cosmology: dark matter and value of omega; ideal design of the universe; question of whether the universe has a point.