Siemens is a technology company. Co.'s Energy sector provides a range of products, solutions and services for generating and transmitting power. The Healthcare sector provides customers a range of medical solutions across the treatment chain. The Industry sector supplies products and solutions for industrial companies, primarily in the process and manufacturing industries. The Infrastructure & Cities sector provides a range of technologies that accelerates the capabilities of metropolitan centers and urban infrastructures. The Investments segment is comprised of Co.'s equity stakes in other companies. The Financial Services segment provides business-to-business financial solutions.

Siemens Gamesa Renewable Energy is a holding company. Through its subsidiaries, Co. is engaged in the business of renewable energy sources, primarily wind power but also including solar energy where its acts as a supplier and manufacturer of technological products, installations and services. Co. is organized along the lines of: promotion, construction and sale of wind farms, engineering, design, manufacture and sale of wind turbines, manufacture of thermic and photovoltaic solar components, promotion and sale of photovoltaic solar farms. Co. also participates in both Spanish and European working groups aimed at establishing priorities for its sector's research & development work.