The new Expropriation and Determining of Compensation Act (Official Gazette, No. 74/14, 69/17, 98/19) entered into force on 26 June 2014, with the exception of Articles 57, 58 and 59, which entered into force on 1 January 2016. Thus, after 20 years of its existence, the former Expropriation Act ceased to be valid (Official Gazette, No. 9/94, 35/94, 112/00-Decision of the Constitutional Court of the Republic of Croatia, 114/01, 79/06, 45/11, 34/12). This paper will analyze the abovementioned Act with a particular emphasis on significant changes it has made in the legal regulation of the expropriation system, as well as its amendments implemented by the Amendments Act to the Expropriation and Determining of Compensation Act (Official Gazette, No. 69 / 17), which entered into force on 22 July 2017. The most significant and at the same time (especially in practice) the most controversial change introduced by the Amendments Act is a completely new institute in the expropriation procedure, which is the institute of interim administrative act on expropriation (preliminary decision) that is dealt with in detail in one of the central chapters of this paper. According to the Amendment Act to the Expropriation and Determining of Compensation Act (Official Gazette, No. 98/19), which entered into force on 1 January 2020, expropriation tasks have been entrusted to the competent county offices, because the state administration offices in the counties have ceased to operate as part of the reform of the entire state administration system aimed at decentralizing the performance of tasks. Thus, the Expropriation and Determining of Compensation Act was originally adopted in 2014 with the main goal of accelerating expropriation procedures in the Republic of Croatia. However, during its relatively short application in practice, it has become clear that expropriation procedures are still taking too long, which is a major obstacle in the implementation of investment projects, as well as in the use of EU funds. Therefore, the amendments that were really needed were drafted, but it is a pity that the Amendments Act to the Expropriation and Determining of Compensation Act (OG 69/17) did not produce better solutions to many issues that still remain open.