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There are many York-based and nation-wide voluntary opportunities listed in the Clinical Psychology section of the document in the link below, but do also search for your own.
Work experience for psychology professionshttps://www.york.ac.uk/media/studenthome/workandvolunteering/infosheets/workexperience/Psychology-work-experience.pdf
You are encouraged to gain experience early on, but please make sure to balance carefully any volunteering with academic and social lives (you are unlikely to gain entry into a DClin couse without good grades).
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