SEC Commissioner Daniel Gallagher warned Thursday of hazards in the bond markets for retail investors.

In a speech touching on both government and corporate bonds before a Municipal Securities Rulemaking Board conference, Gallagher said there is a need for greater transparency.

“The opacity of the markets, especially given the lack of a centralized collection and continuous dissemination of bid/ask quotes—that is, pre-trade price transparency—makes it difficult for retail investors to feel confident that they received the best execution,” Gallagher said.

He urged the MSRB to finalize a rule for municipal securities transactions that would require dealers to seek the most favorable prices for clients. He noted retail investors cannot be sure they are getting the best price today for corporate bonds or munis.

While electronic trading is on the rise in the bond markets, he noted that corporate bond desks at some major Wall Street firms continue to execute trades primarily over the phone.

“It is still common for investors to place corporate and municipal bond trades by calling their broker for a quote, without much insight as to whether they are receiving best execution and a fair price,” Gallagher said.

He pointed to a weakness in the private bond area at the SEC as well, noting the agency has no staff focused solely on the corporate bond market.

He wants the commission to do a major study on corporate bonds, much like it did on municipal securities from 2010 to 2012.