That's part of the problem - you're apparently thinking "same airline" when you should be thinking "same alliance". Pardon me if you already know this and I'm being Mr. Obvious, but are you familiar with the three major airline alliances: Star Alliance (referred to here as *A), Skyteam (ST), and oneworld (ow)? You don't have to fly the same airline - you just have to pick one alliance and then pick one - and ONLY ONE - airline program in that alliance.

*A: US carriers are United, and US Airways including the America West (HP) part of it. Other North American carrier: Air Canada. European carriers include (partial list): Lufthansa, bmi, Swiss, Austrian, LOT Polish, TAP Portugal, Spanair, Scandanavian, and affiliates. Also several Asian carriers (Thai, Singapore, Air New Zealand) and one each South American (Varig) and African (South African) carrier.

ST: US carriers are Continental, Delta, and Northwest. Foreign carriers include Air France, Alitalia, KLM, Czech, and Aeroflot. Also other North American carrier: Aeromexico. Asian carrier Korean.

ow: Only North American carrier is American, so perhaps less of a good choice if you have varied destinations or don't like O'Hare. But they do go pretty much everywhere. European carriers include Finnair (you're going to Finland), British Airways (cannot earn on American Airlines program when flying US-UK, but can earn on connections UK-Europe), Air Lingus (but leaving the program in early 2007), Iberia. South America: LAN. Asia/Pacific: Qantas, Cathay Pacific.

If you're flying to all the destinations you're mentioning, I can't believe you can't get at least first-level elite status (25,000 miles flown) level if you book all your travel into one alliance.

For example, choose *A and join ONE program - let's say United. UA has pretty good choices out of Logan. Probably can get to where you're going in CA nonstop or one easy connection. The old America West part of US has a hub in PHX so nonstop from Boston to there. Lufthansa has good service to Germany from Boston and a lot of connections from Frankfurt and some from Munich to other European cities, so that should make Finland not too bad. Illinois - UA's biggest hub is Chicago so you're set there. FL, GA, TX, OH on UA you're connecting probably in Washington Dulles but some of those might be easier on US. Credit all of those trips to your United Mileage Plus account - do NOT use a US account for US, do not use a Lufthansa account for LH, etc. You would definitely hit Premier (2P - *A Silver) and likely hit Premier Executive (1P - United mid-level and *A Gold top-level) easily. But if you spread the mileage around different programs, you wouldn't get elite at all.

Skyteam would also be a good choice, and given you have Georgia on the agenda I'd probably say join Delta's program. But fly Delta, Continental, and Northwest, whichever is cheaper/more convenient for your domestic trips. DL has a fair amount of service to non-hubs out of BOS since Boston is a "focus city" for them. To Europe, NW/KLM have flights to Amsterdam with loads of KLM connections elsewhere in Europe. Alitalia has Milan flights with MXP connections. Continental has a fair amount of destinations out of Newark one short flight away from BOS. Again, credit all of these to just one program - probably Delta.

Or oneworld - ow could be good despite my "don't like AA" comments. You can get to the coast nonstop on AA from BOS, I think still. Also European connections via LHR using BA onward (remember don't use BA to fly transatlantic if accumulating miles in AAdvantage). Combine AA to LHR onto Finnair to Finland. Of course a big downside of oneworld is so many connections through connection-and-carryon-unfriendly Heathrow. AA gets you to Dallas and Chicago nonstop and via 1-stop elsewhere in the States. In this scenario credit everything to American.

I'd recommend either Skyteam or *A over oneworld based on these factors: multiple US-based carrier choices rather than just one, and multiple European hubs that have major connections. Also ST and *A don't have the restricton against earning transatlantic in a USA-based program from an European-based carrier that makes BA US-UK worthless to AA members (and conversely, AA US-UK worthless to BA members).

If you think that you could hit 50,000 BIS (butt-in-seat) miles in one alliance, I'd then narrow it down to *A. 50,000 in United's program gets you mid-level elite on United like it 50k does on anybody else. But mid-level elite on United (or on most *A carrier programs) gets you top-level Alliance-elite, Star Alliance Gold. That gets you lounge access on international itineraries. 50K-level elite in the US-based Skyteam programs (CO, DL, or NW) only gets you lowest-level alliance-level Skyteam Elite instead of Skyteam Elite Plus. So no lounge access.

Focus on one alliance (or even on two if you think you can get 75,000 BIS miles in a year). Orbitz is great for finding itineraries in one alliance, including mixed-carrier-within-alliance flights - their Advanced search options under "Preferred airlines" has an option for "Preferred Alliance".

If you do think you could fly 75K miles per year but not 100K, I'd recommend mid-level in *A via UA and low-level in ST via DL, CO, or NW. 75K all in one alliance would still only be mid-level on UA (or the upper-mid on US). 75K on ST would get you top-level on DL/CO/NW but then you'd be nothing on anybody else. 50K *A gets you alliance top-level and international lounge on *A as well as the quite decent mid-level UA benefits, while the 25K in a ST carrier still gets you some elite benefits as to seating, check-in priority, some chance at upgrades, etc.

Your travel pattern sounds like 25k is a cakewalk, 50K is likely, and 75k is quite possible if you focus. Given the multiple airline choices within *A and ST, it should be easy to stay within your chosen alliance and still get good fares and routings.