You can set up taxes in the system if the services you provide are taxable. Taxes are dependent on three things:

  1. Create a tax rate for the company
  2. Assign the tax to a customer in the customer details page --> Additional tab
  3. The service needs to be taxable

These three factors give you complete control on collecting the applicable taxes. You can define multiple tax rates if you clients are in different tax jurisdictions. Keep in mind that a customer can only be assigned one tax rate at a time.