The paper addresses the issues of appropriateness and overall effectiveness of endeavours undertaken by selected countries (France and Russia) in the area of preventing, combating, and reducing illegal migration and criminality of foreign nationals. Analyses of the overall body of experience gained by those countries, often struggling with far more serious problems than ours, make it possible to highlight a variety of approaches to the issues under study, along with identifying new, frequently more effective ways of resolving them. In the section dealing with the French solutions, the author focused on those that are aimed specifically at preventing and combating illegal migration, mainly in the form of illegal residence in France. This is due to the fact that criminal offences committed by foreign nationals in France comprise primarily those related to illegal residence or illegal entry into the country. An in-depth review of the available instruments, mainly on the basis of specific regulations comprised in the Code of Entry and Residence of Foreign Nationals, in conjunction with the provisions regulating their right to claim political asylum, allowed to identify certain specific French solutions which might well be deemed good practices, with a view to having them considered for a prospective transposition into the Polish legal system, specifically into administrative and criminal law. When assessing the French regulations in terms of good practices, it appears prudent to consider their prospective transposition into Polish criminal or administrative law, especially with regard to the following areas. First of all, one would need to consider the option of imposing a lifetime ban on the entry into Poland for committing an offence related to illegal migration, but also with regard to other common offences. It is essential in terms of combating illegal migration, to have any individual conduct involving aiding or facilitating a third party’s illegal border crossing, contravening the law regulating the length of residence, or illegal residence in other countries of the Schengen Area, or in other EU Member States, duly criminalized, and not on the territory of Poland only. Another key solution at hand consists in the option to impose a ban on residence in France, also issued in the form of an administrative decision by the Minister of Internal Affairs, which might also apply to those individuals who are not currently residing in France, or those who have never held such residence do date, whereas might be deemed potential threat to public order. In the section dealing with Russia, the author aimed to address specific projects designed to combat illegal migration of foreign nationals and criminality at large (including organized crime) undertaken in that country. It was established that the Russian Federation was actively involved in combating both phenomena. In terms of preventing and reducing illegal immigration into the Russian Federation, several specific projects have been undertaken. In particular, The Concept of State Migration Policy for 2025 was developed, which sets out the objectives, principles, tasks, key directions, and specific constraints in the implementation of state migration policy across the country. It emphasises the need for the introduction of a number of modifications of legal, organizational and social nature, aimed specifically to radically restructure a number of areas within overall state migration policy. Several amendments were made to the Russian Penal Code of 1996, pertaining to illegal border crossings, organizing illegal migration, and others, as well as to the Code of Administrative Breaches of the Law of 2001 (i.e. a series of offences in breach of border security, visa procedures, etc.).