Some of Tom Roeleveld's photos are available to use free as they are used under a Creative Common Licence. Each photo on Tom Roeleveld's Flickr page states the type of licence used for that particular photo. The photo's are generally licenced using a Non-commercial Creative Common licence, usually the Attribution-NonCommercial 2.0 Generic License. None of the photos used with this type of license may be used comercially.
Photos may be used for free, if it's not being used commercially. However, there are some rules: The photographer, the title and a link to the specific photo on Flickr must be mentioned on the page where the photo is used. An example:
Commercial Use of the Photo
To use a photo commercially a license needs to be purchased. To get more information regarding licenses, please use the contact form.
More information regarding Creative Commons licenses.