Copyright permissions
Copyright refers to the right to copy and use a piece of art work. Copying most commonly happens in digital illustration when someone right clicks on a drawing, clicks copy, and then pastes it to a different platform. Whether this is copied onto a website, a social media post, or in powerpoint, it is an infringement of the creators copyright. In other words, it is against the law. Despite this, my images are copied and used a lot - with the majority of people assuming if you can access it online, it is free to use.

But I do want to promote accessibility of my images. So, what I generally say is that if you are not using in private work, for a company you own (including posting on an instagram page where you have a business website), or for overt commercial gain, then I am ok with my images being used. This is known as non-commercial use.

I don't ask for renumeration for NHS work etc, but ask you consider signing up to Patreon if you find use in my work and can afford to.
If you are a business, private health care, CIC etc. You can contact me to licence work, or the easiest way is to sign up to an appropriate tier on Patreon or email me on creative.cp@outlook.com

Non-commercial use (public services and charities): I am happy to give permission for clinical use and in training presentations. I actively encourage distribution for the social justice focussed illustrations. I always welcome Patreon subscription as a thanks. 
Commercial use (businesses, CICs, private healthcare companies, paid consultation): You need to buy the licence to use, either through Patreon subscription for the duration of use, or private arrangement if on websites, books, training that is sold for significant amounts of money. 
Guest lecturers on university courses: Please do use and sign up to Patreon if you can. 
Printing off and sticking on your wall: Go ahead!