The City of Calgary will examine possible changes to bylaws to ensure not all massage businesses are treated the same.

Ald. Gian-Carlo Carra says the laws currently do not differentiate between therapeutic massage and other, not-so-reputable types of massage.

City hall shouldn't lump legitimate and illegitimate businesses in the same basket, Carra told CBC News, whether they are run by a registered massage therapist, a relaxation massage business or a massage parlour that can be a front for prostitution.

Calgary police estimate there are 50 to 60 brothels operating in the city under legal licences.

"At the same time we want to make sure that we're not driving illicit activities underground. We want to be able to sort of figure out how to control their proliferation in a way that makes sense for neighbourhoods and maybe even control the location of where they go," Carra said Tuesday.

One way to stop the spread of illicit massage parlours is through changes to licensing rules, Carra said.

City officials, working with police, are expected to file a report on the issue by next May.