WIPO facilitates international integration through 22 intellectual property treaties dealing with registration processes. Integration can occur at substantive and procedural levels through harmonization of laws. The Paris Convention allows for trademark, patent, and design registration within member states. The Patent Cooperation Treaty and Madrid Agreement/Protocol allow for centralized international registration of patents and trademarks. WIPO is working to further harmonize laws through treaties like the Patent Law Treaty but has faced challenges due to sovereignty concerns among member states.