What kind of visas would be appropriate for my employees if I am looking to expand my business to the United States?

As a lawyer, I would advise that you explore various visa options available to your employees based on the nature of their work, qualifications, and intended length of stay in the United States. Here are some common visa categories that you may want to consider:

1. H-1B visa: This visa category is for foreign workers who will be employed in a specialty occupation, which requires a bachelor's degree or higher in a specific field. To qualify for an H-1B visa, the employer must demonstrate that the position cannot be filled by a U.S. worker and that the employee meets the qualifications for the job.
2. L-1 visa: This visa category allows a U.S. employer to transfer an executive, manager, or specialized worker from a foreign office to a U.S. office. To qualify for an L-1 visa, the foreign worker must have worked for the foreign company for at least one year in the past three years and the U.S. and foreign companies must have a qualifying relationship, such as a parent-subsidiary or affiliate relationship.
3. E-2 visa: If you are looking to invest a substantial amount of money in a U.S. business, you may be eligible for an E-2 visa. This visa category is available to investors from certain treaty countries who are seeking to develop and direct the operations of a U.S. business in which they have invested a significant amount of capital.
4. TN visa: If your employees are citizens of Canada or Mexico and are working in certain professional occupations, they may be eligible for a TN visa under the North American Free Trade Agreement (NAFTA).
5. O-1 visa: If your employees have extraordinary ability in their field, they may be eligible for an O-1 visa. This visa category is for individuals with exceptional talent in the sciences, arts, education, business, or athletics.

It is important to note that each visa category has its own requirements, limitations, and processing procedures. Additionally, it is recommended that you work with an experienced immigration attorney to determine the most appropriate visa options for your employees, and to assist with the visa application process.