In the United States, several work visas require a petition to be filed by a U.S. employer or a qualifying agent. These are known as petition-based visas because they require prior approval from the United States Citizenship and Immigration Services (USCIS) before the prospective employee can apply for a visa at a U.S. Embassy or Consulate. 

 Below is a list of some common petition-based work visas: 

1. H-1B Visa: For specialty occupations that require at least a bachelor’s degree or its equivalent in the field of specialized knowledge. 
2. H-1B1 Visa: Similar to the H-1B, but specifically for nationals of Chile and Singapore.
3. H-2A Visa: For temporary or seasonal agricultural workers. 
4. H-2B Visa: For temporary or seasonal non-agricultural workers. 
5. H-3 Visa: For trainees or special education visitors who are coming for training other than graduate medical or academic. 
6. L-1A Visa: For intra-company transferees who work in managerial or executive positions in a company located outside the U.S. and are being transferred to a U.S. company. 
7. L-1B Visa: For intra-company transferees who possess specialized knowledge. 
8. O-1A Visa: For individuals with an extraordinary ability in the sciences, education, business, or athletics. 
9. O-1B Visa: For individuals with an extraordinary ability in the arts or extraordinary achievement in the motion picture or television industry. 
10. O-2 Visa: For individuals who will accompany an O-1, artist or athlete, to assist in a specific event or performance. 
11. P-1 Visa: For individual or team athletes, or members of an entertainment group that are recognized internationally. 
12. P-2 Visa: For artists or entertainers who will perform under a reciprocal exchange program. 
13. P-3 Visa: For artists or entertainers who perform under a program that is culturally unique. 
14. Q-1 Visa: For participants in an international cultural exchange program for the purpose of providing practical training, employment, and the sharing of the history, culture, and traditions of the applicant’s home country. 
15. R-1 Visa: For religious workers to be employed by a non-profit religious organization in the U.S. 
16. E-3 Visa: Similar to the H-1B, this visa is specifically for nationals of Australia in specialty occupations.