This chapter examines the contract for work and services which is governed by Articles 363–379 of the Swiss Code of Obligations. This chapter commences with the sources of this contract, its characteristic elements, its delimitations with other contracts as well as the diverse forms of this contract. This chapter then moves on to discuss the formation of the contract for work and services before discussing in detail the obligations of the contractor, namely the obligation to carry out and deliver the agreed work and the duty of diligent performance and other ancillary obligations, the contractor’s non-fulfilment of these obligations as well as the client’s obligation to pay the price. In this context, the contractor’s warranty of conformity is analysed in detail. Finally, this chapter explores the end of the contract for work and services either due to the client’s right to withdraw or subsequent impossibility.

Chapter 6 deals with the final motion relating to a treaty, ie its destruction (phthora). To this effect, the chapter starts with an examination of withdrawal from a treaty, even when no such withdrawal clause exists, and the possibility of revocation of a notification of withdrawal. This last one rose to prominence with Brexit and the Wightman cases. The situation is further complicated by the fact that anomalous situations can also occur where termination or suspension may be required. Chapter 6 does not examine only the existing grounds of termination/suspension under the VCLT, but also certain grounds that despite not being included in the VCLT have been argued to provide additional, customary law-based grounds for termination/suspension. Two kinds of motion are examined in this context: i) the motion between the VCLT and non-VCLT alleged grounds for termination/suspension, ie the connections, near identity and in some cases suggested absorption of one ground by another; and ii) the motion between, on the one hand, the grounds for termination/suspension, as a subset of treaty law, and, on the other hand, other sets of rules such as State responsibility.