There's a one-word theme for the 2012 tax year: uncertainty. Chief among the reasons are the sky-high exemptions on the estate tax, the lifetime gift tax and the generation-skipping tax. All are currently set at $5 million, but they are headed for expiration at year's end. Most planners expect that these taxes and others - including taxes on capital gains and dividends - will be going up next year, though no one knows for sure. And that's the rub.

"The big question is whether the Bush-era tax cuts will expire at the end of 2012," says Eleanor Blayney, consumer advocate for the CFP Board. "So there's a lot of uncertainty. A lot of us assume that, one way or another, taxes will go up. And if not directly, then we may lose deductions."

After speaking with and learning from planners around the country, Financial Planning has gathered a list of top tax strategies for 2012. Quite a few of these strategies are geared specifically to this year's low-tax-rate environment. Others are tried and true, and bear repeating in any tax year. For as any good planner knows, smart tax planning is not only about choosing the right strategy at the right time, it's also about avoiding bush league mistakes, like the one that befell one high-net-worth family about five years ago.

In this instance, according to the planner involved, several children of modest means became very wealthy upon inheriting assets from their late father. Each child in turn prepared his or her own estate plan. All but one brother signed a plan. "He just never got around to it," the planner says.

About a year after the father died, the son "went to a holiday party, had a massive heart attack at age 49 and died with no estate plan in place," the planner recalls. "His sisters were literally running through the house saying, 'Did he sign the plan? Did he sign the plan?' No, he did not. His estate paid 45 cents on the dollar above and beyond the federal exclusion. More tragically, the old will still named his ex-wife and her child, his former stepchild. It was grotesque. A ton of money went that didn't need to go." All because of one critical misstep.

Planners often don't know for sure which tax strategy could end up being most critical for each client. But, as this case shows, doing something as simple as getting clients to review their estate plans can be just as important as taking advantage of a $5 million estate and lifetime giving exemption.

1. Consider the $5 million estate and lifetime giving tax exemptions.

For the rest of the year, the beneficiaries of anyone who dies won't pay federal estate taxes on the first $5 million value of his or her estate. A gift tax and generation-skipping tax exemption, both at $5 million, were designed to synchronize with the estate-tax exemption. That means that, before they die, clients can give up to $5 million to any individual, including their grandchildren or charity without paying taxes on the money. For couples, the limit is $10 million, with a 35% tax on assets above that amount. The $13,000 annual gift-tax exemption also remains in place and does not count against the $5 million thresholds. By next year, these exemptions could drop substantially.

"It will really be ugly if it goes back to [2002] when it was at $1 million," says Armond Dinverno, president of Balasa Dinverno Foltz in Itasca, Ill.

Some planners say many of their clients have already taken advantage of these exemptions. But others think they pose hidden and dangerous risks. "There are a number of things we leave to our children," Dinverno says. "They include family values, faith and work ethic. I don't think that trading a tax savings for a work ethic or at the expense of creating a trust fund baby is a good choice."

Some of Dinverno's clients have decided it's just not worth the risk to give money too soon to a child or a grandchild, even if the high giving threshold disappears next year. A multimillion-dollar gift, given too soon to someone, can strip away that individual's drive to work, he says.

Dinverno's older clients are more willing to pull the trigger. In these instances, their own children are grown, with well-established careers, families and homes, making the perceived risk lower. "For them," he says, "it's a slam dunk."

2. Channel estate transfers through family limited partnerships.

Planner Andy Berg, co-founder of Homrich Berg in Atlanta, advises his clients to combine the gift-tax exemption with family limited partnerships. "The partnerships are a tool you can use to give away a great deal of wealth, but remain in control of the underlying assets," Berg says.