This is a common concern for expats with long-term leases, employment contracts, or business agreements in Qatar. The general rule under Article 3 of the Qatar Civil Code is that a new law applies to all cases from the date it comes into force. However, crucially, the consequences of actions or dispositions already taken under the old law remain subject to that former law. This means that rights and obligations that arose under your existing contract before the new law took effect are generally protected.
When it comes to legal capacity — for example, if a new law changes who is considered legally capable of entering contracts — Article 4 states that such provisions apply immediately to all persons who fall within their scope once they come into force. Changes in capacity that follow the new law will be recognised going forward.
For matters involving evidence and proof, Article 8 specifies that the law in force at the time an incident or act occurred will govern how it must be proved — so you cannot be required to meet new evidentiary standards for events that happened before those standards existed. Practically, expats should review long-term agreements periodically and seek legal advice whenever significant new legislation is introduced in Qatar, to understand whether transitional provisions may affect their specific situation.
This is general legal information, not legal advice. For advice on your specific situation, consult a lawyer licensed in Qatar.