The strategy and structure of the 100 largest manufacturing firms in Italy over the 1950-1970 period are analyzed. Strategy is classified as to the degree of diversification: single, dominant, related, or unrelated business. Formal management structure (as distinct from legal form) is classified as functional, holding-company, or multi-divisional. Diversification and structure are classified as of 1950, 1960, and 1970. It was found that there has been widespread adoption of the strategy of product-market diversification, with considerable decline in the number of single business companies and a large increase in the number of diversified companies. As the prevalence of the strategy of diversification has grown, there has been increased adoption of the multi-divisional structure. The form, virtually absent in 1950 from the population studied, has been adopted by 48 per cent of the population in 1970. Companies in the drink, oil, paper, and power machinery industries exhibited little tendency to diversify beyond the dominant business category. Firms in the ceramics, chemical-pharmaceutical-toiletry, rubber, textile, electric-electronic, engineering, and printing-publishing industries tended to evolve into related business category. No clear tendency was observed for firms in the food, and metal and mineral industries. Variable financial rewards related to performance measures were absent in Italian multi-divisional companies.