The process of filing a naturalization application is straightforward, and anyone comfortable with the English language and filling out forms could do it without an attorney. An attorney's role in a naturalization application is more about spotting issues that could cause the application to be denied (and your filing fees lost), or more serious issues that could put your legal status in jeopardy. For instance, I always say if you have ever been detained by the police for any reason you should talk to an attorney before filing an N-400. Sometimes people think they don't have a criminal record because a conviction has been expunged or a charge dismissed. Dismissed charges and expunged convictions need to be dealt with proactively on a naturalization application and this should be handled by an attorney. Also, some convictions that do not seem that serious or are misdemeanors under state law can have serious immigration consequences.Another issue that should be handled by an attorney is a trip abroad of more than 180 days. While this does not necessarily preclude a person from getting a green card, it does require analysis and explanation, best done by an attorney.Other red flags include tax issues (late filings, missed filings, overdue payments), separation shortly after receiving a green card through marriage, problems with child support or alimony, or quitting your job shortly after receiving your green card through work.Also, if you have a US citizen parent, at least speak briefly with an attorney before filing. It continually surprises me how frequently it happens that people have automatically derived citizenship through their parents without knowing it. In this situation, you will not be allowed to naturalize because you are already a citizen. This means you lose the money and time spent on the naturalization application, and then have to spend more money and time going through the different process of applying for proof of citizenship.If none of these factors apply to your situation, you could probably file your own N-400 without a problem. I agree with Joseph, however, that sometimes us attorneys can still be useful for simple cases! For instance, sometimes the government will issue nonsensical demands for unnecessary or irrelevant evidence, or an untrained officer will take a mistaken view of the law. In these cases it is faster and much less stressful to have an attorney who sees this sort of thing every day advocating for you. That's my totally biased two cents!