For the most part, any commercial font will need to have a Font Licence purchased in order for you, the Client, to use the font in the logo. Even some Free Fonts will have limitations on Commercial Personal use, so it's important to check the Font Licence for any font used. Before I commit to using a Commercial Font for your logo, I will of course get your permission first! Font licensing is not a black & white situation, so I have written a detailed post on Font Licensing and Font Licenses, which covers the majority of scenarios: An Explanation on Font Licensing & Font Licence Matters for Logo Designers