This ad hoc query maps the use of quota systems and quantitative limits to regulate legal migration across EMN Member and Observer Countries, detailing target groups, establishment methodologies, and the institutional frameworks responsible for setting and adjusting these limits. 

This ad hoc query examines whether EMN Member and Observer Countries apply mechanisms that regulate or limit the number of citizenship or naturalisation applications that may be submitted or processed within a given period. It also looks at possible future changes and at any legal or practical concerns regarding compatibility with the European Convention on Nationality.