Next Sunday, voters in Italy will decide on a referendum presented by Prime Minister Matteo Renzi which would reform the constitution to speed up lawmaking and to produce a more stable government. If the referendum fails to pass, there is the potential for many troubles to develop in Italy. First, much needed reforms for the Italian banking sector likely would be postponed, which would put many banks at risk of failing. Investors are concerned that this could impact banks throughout Europe. In addition, Renzi has said that he will step down if the referendum does not pass. His resignation would likely lead to a period of political uncertainty in Italy, and it could result in more power for a political group which favors leaving the euro. In the wake of the Brexit vote in the UK, investors would be very concerned if they saw the potential for Italy to exit the European Union. The most recent polls show that it may be a very close vote. Investors have reacted to the uncertainty by shifting to safer assets, including U.S. mortgage-backed securities (MBS). Since mortgage rates are set based on MBS prices, the news resulted in improvement. For the rest of this week, news which points to the referendum passing likely would be negative for MBS, and news which suggests a defeat would be positive.