He is the first and only person running for the president of the united states with swiss bank accounts and in foreign countries with tax shelters and tax avoidance schemes.  Romney's father, filed 12 years of tax returns and said that this should be standard.  Romney, his son has only filed one tax return.
Why would anyone need a Swiss bank account, 1) to conceal your wealth 2) or think that the Swiss franc is stronger than the US dollar.  Romney moved his money over under a Republican president.

Romney replied," I am not the money manager, and I don't know where the accounts are."  The day before Romney was sworn into governor, he transfered the money into a money trust under his wife's name, which is a tax haven.  Why would someone running for the highest office in the land, conceal his financials.  Ask Romney, "Have you paid your fair share in taxes?"

related links:
Tax Haven Candidate 

Romney: Ed Show Tax Haven Candidate

George Zornick From the Nation says, "Romney won’t disclose what money he may be hiding overseas, but we do know where his donors put their billions. Ten of the eleven top contributors to Mitt’s campaign (who contribute through political action committees and employees, not directly) abuse offshore tax havens, and some are the most notorious in the business for doing so. Citigroup, for example, has over 1,200 offshore tax havens, and is the sixth biggest donor to the campaign. Nation writer George Zornick went on The Ed Show last night to shed more light on why the presumptive GOP candidate needs to open his books now."