Be careful whom you trust with your finances.

In this post-Madoff world, confusion reigns when it comes to picking a financial professional who will put investors’ best interests first at all times.

Now more than ever, financial advocates say, even as regulators are pushing new rules to protect them, people need to ask some hard questions when choosing an investment professional.

“If you want someone who is only in the business of advice, choose someone who is [only] registered as an investment adviser,” said Michael E. Kitces, a certified financial planner who runs the Nerd’s Eye View blog about the industry.

This summer, the Securities and Exchange Commission adopted a rule-making package intended to “enhance protections” and “preserve choice” for retail investors working with investment advisers and broker-dealers.

The SEC made final the Regulation Best Interest rule, which requires broker-dealers to “act in the best interest of a retail customer when making a recommendation of any securities transaction or investment strategy involving securities to a retail customer.”

By next summer, the SEC is also requiring registered investment advisers (RIAs) and broker-dealers to provide retail investors with “simple, easy-to-understand information about the nature of their relationship with their financial professional,” in Form CRS.

Sounds good, right?

Not to the New York attorney general (joined by AGs from six other states and the District of Columbia), who sued the SEC in September, asserting among other things that the broker rule “undermines critical consumer protections for retail investors.”

Nor to the XY Planning Network, an organization of fee-only financial advisers co-founded by Kitces, which also filed suit to challenge the new regulation.

No matter the outcome of the suits or the SEC reg, Kitces said, “The key question that retail investors have to ask is simply whether they’re working with a broker-dealer or an RIA.”

According to the SEC, brokers execute trades and are paid commissions to buy or sell securities.

Registered investment advisers manage accounts and can advise to buy, hold or sell, and can make some of those decisions for compensation, the SEC says.

Some are both. RIAs are registered with the SEC or state authority. Broker-dealers are most often members of the Financial Industry Regulatory Authority.

The difference is RIAs are fiduciaries and broker-dealers are not, the RIA firm Frontier Wealth Management said in a blog post.

The National Association of Personal Financial Advisors, which promotes fee-only financial planners and opposes the new reg, says a fiduciary is “a professional entrusted to manage assets or wealth while putting the client’s best interests first at all times.”

The organization encourages investors to ask the professional if they’ll sign a fiduciary oath, said NAPFA spokeswoman Angela Armijo. “If they won’t or can’t, the investor should move on.”