STEM S.A. was founded in 1992 and since then has performed many major and significant projects. During the first years of its operation its registered name was STEP S.A. The change from STEP to STEM took place in 1998. One οf its founding members is Civil Engineer Athanasios Froussos, who works in the field of repairs and strengthening of buildings and construction projects since 1979.

During its years of operation the company has performed a significant number of specialized projects all over Greece.

The company has permanently employed teams of experienced technicians and privately owned modern equipment covering the whole spectrum of its line of business.

It has privately owned premises enabling maintenance of its equipment and construction of specific parts of certain undertaken projects.

In 2016, the Company was absorbed by GRAOUTEC S.A., a Technical Company with wich STEM S.A. was already cooperating. The Company now operates under the title GRAOUTEC S.A. at the same address while also maintaining the same contact info. The Company has a Contractor's Certificate and is ISO 9001 certified.