The most common failure in academic writing is the failure to establish a clear thesis. The thesis is the reason for being for any academic paper. It gives direction to your writing and lets the reader (who is very frequently the one evaluating your work — remember how nice it is to please this person) know what the heck it is you're going to talk about.

Many professors demand a specific thesis sentence. An advanced writer can often give a good idea about what his or her thesis is without relying on a single sentence to define it; however, even when such a sentence doesn't physically appear in the final paper, chances are that the writer wrote one before beginning the work in order to be cognizant of the paper's main theme.

While it's true that the thesis is a tool for the reader, you should also be aware that the thesis is a tool for you as you write. By constantly referring to your thesis, you can more easily keep your paper on-topic and make a cleaner, more intelligent-sounding presentation.

Often in the sciences (and frequently in any research paper), the thesis will come from a hypothesis formed before you do your research. A hypothesis is the idea you believe will be proven (or disproven) by the experiment or research you do. Once you've done the research, your thesis may discuss if your hypothesis was proven correct or incorrect. It should also probably explain any implications of your research.

A thesis on a literary topic may be what you feel is a message of the work, or the significance of a theme or motif in the work. It should be a subject that is meaningful to you and relevant to the topics you've uncovered in your research. Most importantly, it needs to be a subject you are interested in. If you enjoy the subject, you'll have a much easier time writing about it.

Developing exactly what you want to say about an assigned subject can be a difficult task, but finding and using a solid thesis can make or break a paper, so it's worth it to put a lot of work into writing your thesis. If your paper assignment comes in the form of a question, you can often rephrase the question as a statement for your thesis. If this doesn't work, and you feel you are stuck, you may want to try writing down all your thoughts on the subject. Once you've seen what all your ideas are, you can choose a statement that will allow you to include the greatest portion, or even better, the highest quality of the ideas you wrote down. Using this method, you may have half your paper written already. All you need to do is organize it and smooth out the transitions. Once you have chosen a thesis, you are ready to get approval from your professor. Many papers, such as a master's or doctoral thesis, require that you get formal approval from your advisor. Even if your paper doesn't require it, however, very few professors will object if you explain to them what your thesis is and how you plan to approach the discussion in order to get the professor's input on the subject.

If you are required to write a formal proposal, you will probably also be given a set of guidelines for the proposal. Such proposals should include your thesis statement, the approach you will take toward your research, the sources you think you will use, and frequently the organization your paper will use. Many of these items are variables, so don't worry if your paper evolves such that the end result is different than your initial proposal. Professors normally accept that a proposal is a fluid document, not something chiseled in stone.