Legal Question in Real Estate Law in Illinois

With a deed in your name, showing that you hold title.

A deed or an abstract of title ( title report). In some circumstances a land contract to purchase.

In some circumstance, onwership of the beneficial interest in a trust, although tecnically that is not legal ownership of the land and improvement.

You would have to do a title search. Typically, this is done by a land title company, like Attorneys Title and Guarantee Fund, e.g.

To whom are you needing to prove title? If you inherited something maybe the will, or a deed from the executor -- or if you purchased it a CURRENT ownership search (done by a title company), but it helps to know your audience.....

The only way to PROVE ownership of real estate is to do a title search. A deed, on its own, proves nothing. I can give sign a deed conveying the Sears Tower to you (no, I do not care that they changed the name). You now have a deed to the Sears Tower. But, unless I owned the Sears Tower, that deed is worthless. And unless the person who conveyed the property to me owned the Sears Tower, any deed to me is worthless, and so on and so on. So you need to follow what is called the chain of title back several decades, depending on the circumstance to PROVE ownership of real estate.