Is there a program to decompile Delphi?

Languages like Delphi, C and C++ Compile to processor-native machine code, and the output executables have little or no metadata in them. This is in contrast with Java or .Net, which compile to object-oriented platform-independent bytecode, which retains the names of methods, method parameters, classes and namespaces, and other metadata.

So there is a lot less useful decompiling that can be done on Delphi or C code. However, Delphi typically has embedded form data for any form in the project (generated by the $R *.dfm line), and it also has metadata on all published properties, so a Delphi-specific tool would be able to extract this information.

I don't think there are any machine code decompilers that produce Pascal code. Most "Delphi decompilers" parse form and RTTI data, but do not actually decompile the machine code. I can only recommend using something like DeDe (or similar software) to extract symbol information in combination with a C decompiler, then translate the decompiled C code to Delphi (there are many source code converters out there).

You can use IDR it is a great program to decompile Delphi, it is updated to the current Delphi versions and it has a lot of features.

Here's a list : http://delphi.about.com/od/devutilities/a/decompiling_3.htm (and this page mentions some more : http://www.program-transformation.org/Transform/DelphiDecompilers )

I've used DeDe on occasion, but it's not really all that powerfull, and it's not up-to-date with current Delphi versions (latest version it supports is Delphi 7 I believe)