The days of advisors independently managing vast sums for extremely wealthy investors are over, according to a new study saying only 20% of these investors are likely to give their financial advisors full discretion.

Families with assets over $200 million are skittish about handing over the reigns to advisors, according to a new study released by the Institute for Private Investors on Thursday.

Instead, approximately 36% of ultra-wealthy families say they must approve all decisions affecting the composition and management of their portfolio, while 44% give their advisors limited control.

“Post the financial crisis, investors have realized they cannot abdicate the ultimate responsibility for overseeing their wealth,” said IPI's executive director Mindy Rosenthal.  “We are seeing a clear trend toward investors taking an active role in partnership with the advisor.”

Even wealthy families with assets of only $50 million were reluctant to give up control, the study found. Only 32% say they felt comfortable giving their advisors manage their investments without explicit oversight, the institute reported.

Not only are these wealthy investors unlikely to relinquish control, many lack confidence in their current investment strategy. Almost a quarter of the 75 families surveyed expressed major concern that their approach could withstand domestic policy shifts, or worse, a geopolitical crisis.

Yet in spite of these insecurities and the uncertainty in the market, these extremely wealthy investors did not feel pressured to reduce their spending. Only 28% say that they felt the need to reduce their expenses or change their wealth management perspective because of the current economic environment, the study found.

IPI—a subsidiary of Campden Wealth—reached its conclusions based on a questionnaire sent to members during the fourth quarter of 2012. Members have more than $30 million in assets and approximately 40% have asset levels above $200 million, the institute said.