Knowledge Base: Copyright

As a general guideline, copying a portion of up to 10% of a published work is likely within Fair Dealing.  More than 10% may also be fine under certain circumstances such as copying an entire article from a journal, an entire short story, a play, or poem, an essay or a single musical score that was part of a collection, anthology, or periodical publication.  The closer you get to copying 20% of the material or more, the more likely you will need to get permission from the copyright holder.