The research on the international child abduction in the Republic of Croatia is driven by the need for the analyses of the state of compliance of Croatian practice with the international and EU law of international child abduction, in the new legal environment resulted from the Implementation Act enactment, and taking into account the new rules introduced by the Brussels IIter Regulation. The research is focused on certain difficulties, which were pointed out by the ECtHR and identified by the earlier national research. The research sample consist of national child abduction case law instituted in the period from 1 January 2019 until 31 December 2020. The research examines whether the Croatian practice is in line with the general legal doctrines, principles and policies arising from the international and EU law on international child abduction and determines whether it had brought the improvement in relation to the earlier research results from the period prior to the Implementation Act. The analyses within the chapters, involves the determination of the number and manner of conduction of the cases. The discussion assesses the case law in the broad context of legal sources, comparative implementation solutions, the CJEU and ECtHR case law, results of global research and the HCCH and EU operational documents. The introductory chapter explains the research problem and provides the overview of the previous research on the international child abduction. The chapter presents the research objectives, hypotheses and in relation to that, the research methodology. It finishes with the statement on the expected scientific contribution. The second chapter presents the overview of the legal sources regulating the international child abduction. The chapter gives a display of legislative history and summary of the provisions. This is followed by the review of general legislation which complements the core sources of international child abduction. The chapter as well includes the rationale of the interrelation of the legal sources. The third chapter relates to the law applicable to the wrongfulness of the child removal or retention. Previous research showed that the Article 3 of the Child Abduction Convention had been the most quoted provision in the decisions before Croatian courts. It has also identified some difficulties related to the interpretation and determination connected with the applicable law and the notion of child’s habitual residence. The chapter elaborates the semi-autonomous nature of the parental responsibility, habitual residence of a child and renvoi. In order to estimate the possible improvement, the chapter analyses the court practice trough specific issues concerning the sources of parental responsibility, matter of obtaining the evidence on the wrongfulness of the removal or retention and matter of actual exercising of the right to parental responsibility.The fourth chapter deals with the issues of duration of proceedings. The need for assessment of this matter derives from the ECtHR case law in Karadžić v Croatia and Adžić v Croatia, where the severe difficulties regarding the duration and manner of conduction of proceedings before Croatian national authorities were established. Following those judgments, the Implementation Act had introduced provisions regulating the timeframes and other procedural deadlines. The chapter elaborates the initiation of the return procedure, the matter of locating the child, voluntary return of a child and issues related to the initiation and conduction of the child abduction proceedings. The chapter analyses the national practice in specific legal situations related to the Central Authority acting, duration of judicial proceedings, duration of appellate procedures and procedures on extraordinary legal remedies. The fifth chapter processes the topic of concentration of jurisdiction and judicial specialization. The previous national research confirmed that some of the identified difficulties could be related with the absence of the concentrated jurisdiction of Croatian courts. The Implementation Act introduced the rule on concentration of jurisdiction and had determined the jurisdiction of one court to conduct the child abduction cases. The chapter elaborates the pros and cons of concentration of jurisdiction, explains the delimitation of the rules on local and international jurisdiction and touches upon the matter of concentration of jurisdiction for the proceedings triggered by the “overriding mechanism”. The chapter analyses the national practice in specific legal situations related to the absence of judicial specialization and evaluates the possible benefits of concentration of jurisdiction of Centre for Social Welfare and Centre for Special Guardianship. The rule of concentration of jurisdiction is also being analysed in relation to the proceedings on the merits of parental responsibility, procedures for the preliminary measures and enforcement proceedings. The sixth chapter deals with the provisional and protective measures in child abduction proceedings. The provisions on provisional and protective measures were assessed as significant due to being rarely used and often mistakenly interpreted in relation to their scope and effect. The chapter elaborates the rules regulating the scope of application, applicable law, international jurisdiction, recognition and enforcement. The chapter analyses the national practice in relation to provisional measures provided by the Family Act and safeguards provided by the Implementation Act. The chapter finally touches upon the undertakings and measures for the protection of the abducting mothers. The seventh chapter elaborates the grave risk of harm exception to the return of a child. The analysis of this matter was found to be necessary due to the high rates of child return rejections and strongly emphasized and numerous difficulties in proceedings taking place before the Implementation Act. It was also necessary to assess the new tendencies in the interpretation of the grave risk of harm exception resulted from the Guide to Good Practice on Article 13(1)(b). The chapter elaborates the field of examination of the circumstances from Article 13(1)(b), types of the grave risks and the understanding and assessment of the grave risk of harm exception. The chapter questions the significance of the expert's opinions as evidence on the grave risk. It also analyses different assertions that has been raised in the practice and which relate to the separation of a child from the abduction parent, the adjustment of a child to the new environment, domestic violence over the abduction parent and pandemic. The eighth chapter deals with the enforcement of the return orders. Difficulties related to the enforcement of the return decisions in Republic of Croatia are in most similar to those confirmed at the global level. The difficulties are having the strong repercussion due to the ECtHR decision in Karadžić v Croatia and due to the strong media coverage. The Implementation Act had not introduced the specific rules for the enforcement of return decisions. The chapter analyses the measures in enforcement proceedings which relate to the means of locating the child, child protection mechanisms and those related to the manner of conduction the enforcement proceedings and coercive measures. The chapter analyses the national practice regarding to the procedural and administrative actions in the enforcement proceedings, determination of a place and manner of return of a child and the effect of legal remedies and passage of time on the enforcement. The general conclusions almost completely confirm the research hypotheses. Croatian practice is not fully in line with general legal doctrines, principles and policies arising from international and EU law on international child abduction. This primary refers to the interpretation of the grave risk of harm exceptions, the protection of the child in the return procedure and the enforcement of the return decisions. The hypothesis that the actions of the Croatian competent authorities have improved as a result of the new procedural rules of Implementation Act has been partially confirmed. The improvement was noticed in relation to the actions of the first instance court, Central Authority and Center for Social Welfare, concerning the deadlines and manner of acting consistent to the aims of the Child Abduction Convention. This hypothesis was however not confirmed in relation to the actions of the second instance court, which has often touched on the issues which should be left to the merits of the parental responsibility proceedings. In order to approximate the Croatian practice to the general legal doctrines, principles and policies arising from international and EU law of international child abduction, further amendments and changes of the Implementation Act are needed. The proposals were given trough the special conclusions of each chapter.