Although this was common practice in the early days of the Web, working with HTML tables when it comes to building a webpage layout should be avoided as much as possible nowadays. CSS offers all the tools that are needed to create perfectly dynamic and flexible layouts, so you really should only rely on HTML tables to present actual data. This being said, it happens that you don't have the choice, and that this just what I've learned recently in my work. In the context of a client project, the framework I've had to use (Peoplesoft, an HRIS system) indeed generates HTML pages presenting a structure quite "2000"-ish, consisting in a complex nesting of HTML tables. Moreover, each time you add a component on the page (via the system itself, not when hardcoding it), a system TABLE is create to wrap the object. This can cause obviously a lot of problems, but in this case, my problem was quite specific. A few pages of the system use a well-defined table layout :
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