It's advisable to start with the introduction. This sets the tone for your entire paper, introducing the topic, providing context, and presenting the thesis statement. By crafting a well-structured introduction, you establish a solid foundation for the rest of your essay. It guides your subsequent outline sections, ensuring that each part contributes cohesively to the overall argument. Starting with the introduction allows you to clarify your main ideas and create a roadmap for the reader, making the entire research essay more accessible and engaging.