1982: Continuing its investment policy, OYAK became an equity partner in two companies of the Eti Group - Eti Pazarlama and Tam Gıda - which is one of Turkey's two most important players in the confectionary sector. A construction and engineering management company Oyak İnşaat was established in order to build housing for members. In the same year, OYAK responded rapidly to developments in the capital markets by establishing a brokerage house, Oyak Menkul Değerler.

1984: OYAK became an equity partner of Entaş Entegre Tavukçuluk Sanayi Ticaret, Turkey's first privately owned packaged chicken producer, which launched the Lades brand.

1985; OYAK Renault, a subsidiary of OYAK, has started to produce Renault-9 which had been elected as the car of the year in 1984.

1987: OYAK added the tourism sector to its investment portfolio by acquiring İzmir Etap Hotel.

1988: OYAK's principle of continuously improving member services resulted in an increase in death and disability benefits. Death benefits were set at 20 times the base salary of members.

1989: In order to provide additional income to members during their retirement years, the "Donation Based Retirement Income System" was introduced. A new program was launched that allowed members approaching retirement to borrow up to 80% of their reserves in one year. OYTUR-OYAK Turizm was established to carry out activities in the growing tourism sector.

1990: The number of OYAK members surpassed 117,000. Retirement benefits increased by 3.2 times in US dollar terms since the date of OYAK's establishment. Equity positions were taken in First National Bank of Boston (Turkey), which forms the base of the present OYAK Bank and in Selyak, a player in the petroleum products sector with the Elf brand.