You don't need to buy any additional material. Everything you need to study will be provided by your course provider. Of course, you can buy as you go along if something interests you (I bought Employee Engagement), but additional material should not be necessary to complete the course.

Thanks Charlotte

I can recommend the good old library (when they’re open again!) - I studied one day a month at a local college, and the ability to quickly look something specific up in one of the many suggested books was really helpful. I’d have gone bankrupt if I’d bought all the books that I used very small parts of!