flight to europe with multiple airlines

Are you looking at "multi city" flights (on the airline website, Kayak, Orbitz, Expedia, etc)? These are also called "open jaw" - into one city and out of another. If you are looking at two one-way tickets, that's usually much more expensive, so stop immediately. Go to http://www.kayak.com/flights and choose "multi city" near the top. Put in your first segment as Ft. Lauderdale to Paris, and your second segment as Rome to Ft. Lauderdale. For Ft. Lauderdale, check "add nearby airports" (assuming Miami is OK for you). Leave the third segment blank. Then "find flights" and see what you get. "my worry is that one airlien may have a delayed flight, and then i miss the other flight" If you are booked all on one ticket, the airline is responsible for getting you to your destination if this happens (i.e., they have to figure it out, and it doesn't cost you extra). If you are booked on separate tickets and this happens, you are responsible, both logistically (you have to fix it yourself, with no help from any airline) and financially (last minute tickets are VERY expensive). That's why your instinct is right - it's a bad idea, unless you can accept the risk and are saving enough money to make it worthwhile. I wouldn't do it in your example no matter how cheap it was, but others would. I would only consider this if you planned some time in Paris in both directions - then it's great. Also, if you are checking luggage: if you are booked on one ticket, the higher weight limit applies to the whole flight. If you are booked on separate tickets, the intra-European leg will have much tighter restrictions (potentially very expensive if you go over).

thank you so much for the advice!

What you are doing isn't an open jaw, its piecing together transportation to and from one end destination by using several (two) independently purchased tickets from two separate airlines. I've done it, and am doing it in about 10 days combined with an open jaw ticket; but there is risk. Make sure you have a long layover so if one airline is late you don't miss the other. You are correct in that if you miss your connection with Airline B because Airline A was late you will have to pay a penalty for the ticket change.

Harold did an awesome job explaining how to check/use the multi-city option, and James added great additional info about booking your own, seperate flights. We are using both of these options for our flights to London/Ireland this May. Multi city into London and out of of Shannon Ireland, and a seperate flight from England to Ireland on one of the lo-cost inter EU airlines that you can find on Skyscanner or Whichbudget.com. If you book a connecting flight yourself, allow plenty of time between flights!