The answer is: It Depends! What skills does your team have / how much new learning are they able to do? Are you intending to run the old stuff concurrently with the new stuff or is it a big bang approach? What is the problem domain? That will dictate what are the best tools for the job Are you willing to risk leading edge (which may be buggy) or do you want trailing edge (which may cause upgrade issues in the future) or do you want to play it safe (e.g. go with the next-to-latest version)? Who are your clients / customers? What will they be most comfortable using? Are there off-the-shelf packages that can do what you want which could save you a lot of development time? Stevey T wrote: recommendations on what framework and mythologies/C# version/database methods/Web UI methods, to use Do not use mythologies: they are not real!