18.) Lazard Banker Mattieu Pigasse - Pigasse is both a highly regarded financier and a 'pro-market socialist' advising the Greek government on its debt negotiations.
17 and 16.) Finance ministers Luis de Guindos (Spain) and Michael Noonan (Ireland) - Both countries struggled in the euro crisis and are now taking tough stances on Greece, backing the current bailout.
15.) IMF Managing Director Christine Lagarde - The IMF holds a large amount of Greek debt, and its stance holds huge sway around the world.
14.) Bank of Greece Governor Yannis Stournaras - He's responsible for taking Greek banks' case to the ECB, especially crucial if they need emergency assistance.
next slide will load in 15 secondsSkip AdSkip Ad13.) Minister of Productive Reconstruction Panagiotis Lafazanis - He's a leading light of Syriza's left, and will keep pressure on Tsipras to take a hard line.
12.) EU Commission President Jean Claude Juncker - the most important single figure in the Commission, which makes up a third of Greece's international creditor 'Troika'.
11.) European Commissioner Pierre Moscovici - He's the European Commission's point man on Greek negotiations, and likely to be more friendly to Athens.
9 and 10.) Italy's Matteo Renzi and Pier Carlo Padoan - Italy's PM and finance minister have emerged as Greece's (sceptical) friends in the talks.
8.) German Finance Minister Wolfgang Schaeuble - He's the unofficial leader of the finance ministers taking a hardline stance against Greece.
next slide will load in 15 secondsSkip AdSkip Ad7.) Eurogroup Chairman Jeroen Dijsselbloem - He's charged with chairing the Eurogroup of finance ministers, who'll decide on any Greek deal.
5 and 6.) France's Francois Hollande and Michel Sapin - France is likely to try and play peacemaker between Greece and Germany, and may have a hand in drafting a deal.
4.) German Chancellor Angela Merkel - Though her finance minister represents Germany in the eurogroup, the final decision on Germany's stance belongs to Merkel.
3.) Finance Minister Yanis Varoufakis - Varoufakis is tasked with representing Greece in the negotiations. His successes or failures at bargaining are crucial to the country's future.
2.) Mario Draghi and the ECB - The position the ECB takes on assistance for Greek banks could save or kill Greece's euro membership.
next slide will load in 15 secondsSkip AdSkip Ad1.) Prime Minister Alexis Tsipras - Tsipras is now Greece's most important single decision maker. If he and his finance minister disagree, in the end he calls the shots.