Do I need to send my passport for a non-immigrant 'O' visa application for marriage in the US?

When applying for a non-immigrant 'O' visa for marriage at a Thai embassy in the US, you do not need to send your passport, as the Thai embassies utilize an E-visa system. The application can be handled without mailing your passport, alleviating concerns about travel while waiting for the visa approval. It's advisable to apply at the embassy or consulate that covers your area of residence. Additionally, for those currently in Thailand, it's worth noting that one may need to apply from the US, depending on individual circumstances.