Typically, the investment in an SMA is allocated across one or more existing investment models.

These investment models are provided by investment specialists and they
vary in focus and profile – in much the same way that mutual funds vary in their risk and return objectives.

Within an SMA there will be models with different levels of risk and return,
each with a different emphasis. This diversification ensure that the individual investment needs of all account holders are met.

Some SMAs allow the investor to customise the portfolio by prohibiting certain stock, substituting one stock for another.