A South African diver who undertook diving engagements in the waters of the UK continental shelf was to be treated as self-employed for income tax purposes, and consequently the effect of the double taxation treaty between the UK and South Africa was to entitle South Africa to levy tax on the individual’s income from diving. 
 
The appellant, a qualified diver and a resident of South Africa, undertook diving engagements in the waters of the UK continental shelf in the tax years 2011/12 and 2012/13. The governments of the UK and South Africa were parties to a double taxation treaty; the question arose as to which country was entitled to levy tax on the appellant’s income derived from his diving activities during those two tax years. It was common ground that if the appellant was self-employed, the answer was South Africa. However, whether he was, in fact, self-employed was in dispute.  
 
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