Aberdeen has won an Australian equities strategy mandate which looks to generate returns from S&P/ASX300 companies but avoids the largest 20 stocks.
The ASX20 has a significant skew towards financial companies which make up over 50 per cent of the index and materials which account for almost 20 per cent.
Media Super said the portfolio's high conviction and low turnover approach would bode well for its members' long-term interests.
"We think there are plenty of opportunities for generating alpha outside the top 20 companies, particularly for funds of our size," it said.
"We believe Aberdeen's rigorous investment process and its focus on fundamental analysis will help to uncover quality companies."
Aberdeen Australia managing director Brett Jollie said it was confirmation of the investment manager's track record and experience.