Independent consulting life can be an enviable position to be in. After leaving the consulting industry for a period of time, I returned to consulting life as an independent (for a little over a year). The pros of independent consulting life include more flexible work schedules (relative to traditional consulting firms), challenging work, and control over both what type of work one does and which clients one works for. But there can be some downsides and pressures that what needs to constantly work when working on one's own. Below I list some of the pressures of working on one's own (a subset of these reasons were primary factors for me to return to work within a larger firm):

• Finding new clients while working for existing clients can be tough - There are only so many hours in a day and as an independent, you are marketing yourself. If you are working for a client, you may not have much time for new client development. It is definitely preferrable from an efficiency perspective to sell into existing clients, but logistical reasons may make these options limited (e.g., needs of client change as they move through problem solving lifecycle, and an independent cannot always position themselves as a one-stop shop). Other ways I have seen independent consultants address sales pipeline considerations are by developing a very focused niche (sometimes backed with strong intellectual property), having a extremely strong network of contacts (e.g., with past co-workers and clients in client management positions), using referrals, and lining up clients directly (including timing-wise) from a rolloff from project with the independent's prior consulting firm. Note that I have never used this last option, but I have seen it used, and I recommend if you choose this path that you both use caution and understand the path's limitations.
• Although you can "choose" your clients, sometimes you have to eat too - Probably the hardest thing for me as an independent consultant was cutting across vertical industries (e.g., software, manufacturing, insurance). I have spent my work life almost exclusively in the software and telecom industries (note that this is different from many consulting firms which may have consultants working across many industries early in their careers, e.g., first client dog food manufacturer, second client telecom, third client bank, fourth client valve manufacturer). In any case, sometimes as an independent consultant when an opportunity arises that is outside of your target client profile, one needs to take advantage of the situation and really think hard about how one's background and skillset can be applied to solve the client's problem at hand.
• Landing the first client can be tough - Often when you move to life as an independent, you may have little to no sales pipeline to start with. On top of that, you may have no past consulting references, which creates additional risk in the eyes of new client prospects. Note that getting that first client can easily take six to nine months and the contracting and qualification processes are often very different than those when getting hired as an employee.

All-in-all, I would say that independent consulting is a tough (albeit rewarding) route. As a general rule, I would probably recommend that only experienced persons and those that have attained the principal-level or higher within a traditional management consulting firm pursue the independent consulting path. The predominant reasons for my perspective here are that these professional milestones can often address or balance out (to some extent) issues related to customer references, size of professional network, and in-depth knowledge of sales processes involving complex services and emotional purchasing behavior.