Just weeks after the federal government adopted the biggest tax overhaul in three decades, the effects are rippling through corner offices and boardrooms, with companies large and small dusting off once-shelved plans, re-evaluating existing projects and exploring new investment in factories and equipment.

Specialty drugmaker Amicus Therapeutics Inc. has decided to spend as much as $200 million on a new production facility in the U.S. instead of Europe. Kimberly-Clark Corp., maker of Kleenex tissues, is spending hundreds of millions of dollars to put new machinery in one of its U.S. factories, even as it closes others and cuts thousands of jobs. Aramark , the catering and uniform giant, expects to save nearly $500 million on two recently completed acquisitions.

The rapid adaptation goes well beyond the early announcements of $1,000 bonuses or minimum-wage increases for rank-and-file workers. And this is just the beginning. The U.S. Treasury and the Internal Revenue Service have offered guidance on just a few of the two dozen provisions in the law that will likely require formal regulations. Companies must navigate complex rules imposing minimum taxes on foreign income, tax breaks for partnerships, faster deductions for capital spending and new limits on interest and operating-loss deductions.

“We’re only 30 days into the tax reform process,” Lowell McAdam, chief executive of Verizon Communications Inc., told investors on Tuesday. “We’re all trying to understand the implications and what we can accelerate and how we can accelerate.”

Along with announcing its repatriation of cash held overseas last week, Apple Inc. pledged to invest $30 billion in the U.S. that it had held abroad, despite having to pay $38 billion under a one-time tax on those accumulated foreign profits. Goodyear Tire & Rubber Co. now estimates it won’t pay cash taxes until 2025, because its existing credits will stretch out an additional five years when used to offset taxes at new, lower corporate rates.