This paper examines Japanese employment changes at various career stages along firm, industry, and occupational dimensions, using the 1975 Social Status and Mobility data. Smallest-space techniques depict differences in workers' mobility patterns. Findings suggest the dichotomy of large versus small-firm sectors oversimplifies the labor-market structure, since mobility patterns vary not only ... [Show full abstract] according to firm size, but also to industry and occupation. At all career stages, government employees exhibit mobility patterns different from private-sector workers. Job movements are bounded by industrial origins, as most workers, except those from the traditional primary sector, remain in the same sector after shifts. This tendency is most evident during later career transitions. Workers' destinations are constrained by their past occupations. Mobility barriers between upper white-collar positions and production work are obvious. The persistence of upper white-collar occupations increase during later career transitions, but this is not the case for production occupations.