Congress provided a road map for measures aimed broadly at getting more Americans covered by health insurance and providing more federal safeguards against risky financial practices. But the laws were so broad and complex that executive-branch regulators have wide leeway in determining what the rules should say and how they should be carried out.

In all, the bills call for drafting more than 300 separate rules on a rolling schedule by about 2014, plus dozens of other studies and periodic reports. That may be only the beginning. A recent report from the Congressional Research Service said the publication of rules under the health care law could stretch out for decades to come.

Regulators at various agencies are trying to answer questions like these:

¶How much should a credit-card company be able to charge a shopkeeper for administrative fees when you swipe your card for a purchase?

¶Which types of financial companies are so “systemically important” to the overall economy that they should be subject to greater federal oversight?

¶What services must be covered by all insurers as part of the “essential health benefits” package? And at what point would an increase in an insurer’s premiums be considered so “unreasonable” that state and federal regulators could step in?

These and many other questions are now in the hands of government lawyers, doctors, bankers, accountants, actuaries and other regulatory specialists. With the rules spread across agencies, no one is certain how many employees are working on them, but the number is certainly in the hundreds or higher.

At the Federal Reserve, for instance, most of more than 50 lawyers in the legal division are now spending significant parts of their days on rule-making issues, like the question of how to carry out and enforce the so-called Volcker Rule, named for Paul A. Volcker, the former Fed chairman, restricting banks from making certain types of speculative investments.