The notion of self plagiarism is difficult to grasp, but this definition should help:

"The reuse of significant, identical, or nearly identical portions of one's own work without acknowledging that one is doing so or citing the original work is sometimes described as "self-plagiarism"; the term "recycling fraud" has also been used to describe this practice".

Dellavalle, R. P., Banks, M. A., Ellis, J. I., 2007. Frequently asked questions regarding self-plagiarism: How to avoid recycling fraud. Journal of the American Academy of Dermatology [online]. 57(3), pp. 527. [viewed 7 March 2018]. Available from: doi:10.1016/j.jaad.2007.05.018 PMC 2679117.

Self plagiarism can also be called duplicate or multiple publication or even salami slicing!.
In academic publications, self-plagiarism happens when an author reuses portions of their own published and copyrighted work in later publications, but without attributing the previous publication.
However, in education it happens when a student reuses their own previously written work or data in a new assignment and does not reference it appropriately. This can easily happen when you recycle part of a research proposal in the actual dissertation or thesis itself or parts of your Masters dissertation in your PhD thesis.

Description paraphrased from: Roig, M., 2010. Plagiarism and self-plagiarism: What every author should know. Biochemia Medica [online], 20(3), pp. 295-300. [viewed 21 March 2018]. Available from:

Issues to consider

All of this does not mean that you should never refer to or use your own material, you should just think carefully before doing so. Here are some issues to consider, so:

  • only use as much of the work as is necessary to make your point
  • consider if the previous work needs to be restated to lay the groundwork for a new contribution in the second work
  • provide a full reference to the original work
  • consider paraphrasing your words and contextualising them to your more developed argument while still providing a full reference
  • if paraphrasing alters the sense or clarity of the original then it may make no sense to say it differently a second time, so a direct quote could be justified
  • consider if portions of the previous work need to be repeated to deal with new evidence or arguments

Issues paraphrased from: Samuelson, P., 1994. Self-plagiarism or fair use?. Communications of the ACM [online]. 37(8): pp. 21–5. [viewed 21 March 2018]. Available from: doi:10.1145/179606.179731.

Things to remember
  • if you use material from a previous assignment you must reference it appropriately
  • you should never submit the same essay for different assignments
  • if resitting a course you should not submit the same essay