The introduction of European norms into national legislation can cause certain problems and disagreements.The reasons that can lead to such disagreements, which are mentioned in the statement of the problem, are primarily cultural and historical differences. Countries have their own cultural and historical characteristics that affect their legal systems. European norms may not always take these differences into account, which may lead to differences in the interpretation and application of the law.The reason is the needs and peculiarities of the national economy, because each country has its own economic structure and needs. European norms may not take into account the specifics of the national economy, which may lead to disagreements and cause difficulties in the implementation of certain provisions.European norms may be formulated ambiguously or leave certain aspects uncertain. This can lead to differences in the interpretation and application of the law, as well as to different approaches in court decisions, which is legal ambiguity.Time constraints and the accelerated process of harmonization are also one of the reasons due to differences between Ukrainian and European law. The implementation of European norms can take place at a fast pace, which can make it difficult to adapt and ensure full compliance with national legislation. This can lead to ambiguities and inappropriateness in the legal system.And integration with European law can create challenges in ensuring a unified mechanism for control and dispute resolution. Differences in the interpretation and application of European norms can create problems in resolving disputes between the parties. Therefore, the lack of a single control mechanism is also a reason.Ukrainian contract law needs legislative adaptation. After all, the implementation of European norms requires significant changes in national legislation. This can cause difficulties and require time and resources to implement the necessary reforms.One of the reasons is the lack of full compliance. Ukraine may have difficulties in achieving full compliance with European norms due to various factors, such as backwardness in the development of the legal system, corruption, insufficient legal culture, etc. This can lead to unresolved issues and disagreements with European law.The next reason is the implementation of requirements and standards. Harmonization of contract law with European norms requires the introduction of new requirements and standards. This can be a challenge for government bodies, lawyers, courts and other participants of the legal system, who must familiarize themselves with the new rules, acquire the necessary skills and abilities to apply them.Harmonization of contract law to European standards may also require significant financial costs. This is due to the need for reforms, training of specialists, development and implementation of new laws and legal instruments. The government and other stakeholders must commit sufficient resources to ensure successful harmonization, which is a challenge.The reason for the discrepancy between domestic and European law is the interaction with other branches of law. Harmonization of contract law can affect other areas of law, such as economic, civil and labor law.Changes in one area may necessitate changes in the corresponding areas, which may cause complications and disagreements in their interaction.Harmonization of contract law requires broad public support and involvement. This means the need to inform citizens, businesses and other interested parties about the changes, hold consultations and take into account their opinions and suggestions. Support and involvement of society is needed. Despite these challenges, the harmonization of contract law of Ukraine with European law remains important and necessary. This will contribute to the creation of a single legal space, increased protection of the rights of citizens and enterprises, development of trade and investments, and improvement of justice.However, it is important to take into account the specificities and needs of the country when implementing European norms, ensuring a balance between global standards and national realities.