Strongly recommended: LLC, or limited liability company. First, while you could legally have a partnership, you really want to have either a corporation or an LLC to protect the partners' personal assets (like homes and bank accounts) from business-related liability: both LLCs and corporations will do that, while a partnership affords much less protection.(Note that the protection afforded by an LLC or corporation, while considerable, is not absolute: the owners can still be liable for any obligations they personally guaranty, on many "corporate" or "business" credit cards, for certain "fiduciary" taxes if they are the person in charge of them (basically sales tax and employee tax withholding), and for any wrongful acts they personally perform, like running someone over while driving for work or a company car.)Between a corporation and an LLC, there is little, technically, to choose between--both afford the same liability protection, and you can get the same tax treatment with either. However, an LLC has two major advantages: 1) less paperwork and reporting--a big deal for a small business, whch would rather focus on marketing and providing services; and 2) more flexibility about allocating profits, tax losses (if any), and management power--you can allocate these things any way you like, so long as it is reflected in the "operating agreement" governing the LLC.As to tax treatment: speak to a tax professional, but generally, you will want to choose "pass through" or "partnership" treatment to avoid "double taxation"--I know that's what I've done with the two LLCs (one with three partners, one solo) that I have.