New Delhi, May 16 -- In the sleepy world of trust planning, the topsy-turvy stock market is creating big tax-savings opportunities.

While irrevocable trusts are permanent structures, the assets within them are flexible and can be swapped at any time with different similarly valued assets-a strategy worth considering during times of extreme swings in market values.

"Asset swapping often falls between the cracks," says Ed Renn, of counsel on the private client and tax team at Withers. "Some people are knocking around with trust structures from years back and may not be proactive when it comes to managing assets in the trusts."

Swapping assets is often part of estate planning for wealthy taxpayers aiming to minimize exposure to the 50% es...