The interpretation of a will is indeed a delicate matter. The government committee that developed the Wills Act (SFS 1930:104) described it as an area that ”offers particular difficulties”. When there is a will to be executed, however, the difficulties must be overcome. Frequently, a great deal of time has elapsed since the will was written, which may have led to several changes in different regards. For example, the testator may no longer be in possession of the property named in the will, or changes in the circle of legatees might have occured. When a will is to be interpreted, one must identify the actual underlying intent of the provision. If that is not possible, the executor must ask what the testator’s hypothetical intent would be in the particular situation. Hence, the interpretation process is strictly subjective. If, and only if, the determination of the actual or hypothetical intent of the testator is unsuccessful can one use supplementary presumptions. The Wills Act, which was incorporated almost unmodified into the Inheritance Code (SFS 1958:637), offers a few presumption rules that ”the normal testator” is presumed to approve. This phase of the interpretation is therefore objective. The presumption rules are subsidiary to the actual or hypothetical intent of the testator and ought only be used as an exception. The Supreme Court has, in accordance with this principle of subsidiarity, seldom applied a presumption rule. The court seems to prefer an interpretation of the testator’s intent, even if the intent is rather vague. The court’s case law shows that it does not take much to rebut one of the subsidiary presumptions. Due to the continuing development of society and its constellation of families, the need for development in the law of wills is likewise perpetual. Cohabitants, for example, do not inherit one another according to Swedish law, and thus it is crucial to make a will in favour of a cohabitant to provide for their protection. This paper does not propose a right of inheritance for cohabitants, but rather a presumption rule under specific circumstances: An explicit provision for free disposal of the property left for the surviving cohabitant is presumed to contain a provision for secondary inheritance due to the 3rd chapter of the Inheritance Code. Such a presumption would harmonise with established law and hopefully prevent future interpretation disputes.