They are people "with a record of significant achievement within their chosen way of life that demonstrates a range of experience, skills and competencies... who are able to make an effective and significant contribution to the work of the House of Lords".
Apart from Romanians and Bulgarians, EU nationals have an unrestricted right to work in the UK. The Lords committee wants the government to tighten up on the other non-EU half by imposing a cap on the numbers allowed in.