CLI npm install not working

Can't get CLI npm to work:

Colins-MacBook-Pro:workshop colinlikethewind$ sudo npm install -g plugman
Password:
npm http GET https://registry.npmjs.org/plugman
npm http 304 https://registry.npmjs.org/plugman

etc (ie: successful install)...

Colins-MacBook-Pro:workshop colinlikethewind$ plugman
-bash: plugman: command not found

Plugman is the example here used, but seems to be the case with all npm installs. Can anyone shed light onto this?