# Transaction Costs and Turnover Controls

The Windham Portfolio Advisor allows the specification of a transaction cost vector across all instruments defined in the portfolio. To disregard turnover control, transaction costs are set to zero. This would be the same as constructing and transitioning into the optimal portfolio from an all-cash position.

![Specifying transaction costs](/files/-MEy_vlFYWv9ppLvU5Pk)

To control turnover from the current portfolio allocations, populate the transaction cost column in the Constraints screen by reviewing the Min Max Bounds tab.


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