One after the other, the world's largest governments have unveiled multibillion-dollar infrastructure spending plans as part of an effort to jolt their economies back to life. France's Nicolas Sarkozy is orchestrating a giant rebuilding program, while China's $580 billion spending package has received a nod of approval from the Organization for Economic Cooperation and Development (OECD) as being likely to give a boost to that country's growth. Now President Barack Obama and his advisory team propose to give the U.S. economy a shot in the arm with a giant stimulus package that may amount to as much as $1 trillion.

The new president has already declared on the record that this money will be aimed squarely at the country's infrastructure—the roads, railways, airports, utilities, ports, public buildings and other networks and structures required for the economy to be as productive as possible. The result? The infusion of government cash into infrastructure projects would be the largest since the mid-1950s, when President Dwight D. Eisenhower threw his weight behind the creation of a nationwide highway system.

If this impending flood of infrastructure spending is emerging as the sole ray of sunshine in the gloomy economic environment, the question for financial advisors now is whether there is a way that their high-net-worth clients can profit from it. The dollars themselves will come from the government's coffers, and many will be invested in what are still government-owned assets, such as airports or bridges. In other cases, infrastructure spending may be allocated to highly regulated businesses, such as power utilities—spending may improve the power grid and electricity reliability for the country as a whole, but isn't likely to cause the utilities to become growth stocks and see their price-earnings multiples and valuations explode overnight.

But those constraints don't mean that affluent investors must content themselves with sitting on the sidelines and waiting for the infrastructure spending to trickle down to the broader economy, hopefully sending the whole stock market higher. "I believe this is a very legitimate investment thesis and perhaps even an asset category, if not an actual asset class," says Hans Olsen, chief investment officer of JP Morgan Private Bank.