Fifa is a deeply divided organisation, often on racial and economic lines, and it will take some time to repair the damage done under Blatter's regime. It will take someone with great leadership to heal the divisions and it's not certain anyone really exists to do this at the moment.
Uefa president Michael Platini has been mentioned as a possible successor but Europe have often been perceived as arrogant by some of the poorer nations - 209 nations will vote on the next president. Blatter often pointed out Brazil, England or Italy are no more powerful than Belize, Mongolia and Fiji because they each get one vote and that is the challenge for whoever takes over.
It's not like Fifa will suddenly struggle without a clear leader. They are a huge machine that generates huge wads of cash without really having to work that hard but they have significant work to do to repair their image.
Many countries, led by England, were considering a World Cup boycott and a host of global companies were re-evaluating their association with football. There needs to be significant and meaningful change for sponsors and fans to trust them again. They need to be clean.
Attention will inevitably focus on the World Cups due to be staged in Russia (2018) and Qatar (2022) but it's hard to see a re-vote on these and, ultimately, a change in venue.
Both are well advanced in their preparations and both will have significant legal claims against Fifa if the tournaments are moved and a re-vote taken unless solid evidence is found of any corrupt dealings.
Blatter's resignation will create uncertainty in Oceania. The confederation have long supported Blatter, and last week 10 of the 11 member nations voted for him again. The region has benefited enormously under Blatter's watch with significant investment in facilities and competitions.
But New Zealand, Oceania's biggest nation, went out on a limb to vote against Blatter more out of principle than a belief in his rival Prince Ali bin al Hussein.
It created tension within the confederation, tension that has surfaced at various times over the past 15 years, and distrust.
Blatter's resignation is a good day for football. Let's hope the next few are also good.
5 potential candidates to replace the outgoing FIFA president
Prince Ali bin Al-Hussein
Perhaps the most credible candidate - having stood against Blatter just last week.
Prince Ali gained enough votes to take the election to a second round of voting, but decided to pull out due to the discrepancy between the support he had received and the number of votes the Swiss had attracted.
He has been the president of the Jordan FA since 1999, vice-president of FIFA since 2011 and founded the West Asian Football Federation in 2001.
Michel Platini
The president of UEFA, and a high-profile voice against Blatter since the FBI's investigation into corruption in FIFA.
Platini asked Blatter to resign ahead of last week's election, and praised his decision today as 'difficult and brave', saying he made the right call to stand down.
He has been in office with Europe's governing body since January 2007, and would be a feasible replacement for the Swiss.
Luis Figo
Another great as a player, Figo was due to stand against Blatter in last week's election, but pulled out just days before.
In an explosive statement, he said: "The realm of a sport which gave me everything to become what I am, and to which I now offered to give something back, is hungry for change. FIFA needs change and I feel that the change is urgent.
Senes Erzik
A Turkish former UEFA vice-president, Erzik is currently fourth favourite to succeed Blatter.
He was brought on to the board of the Turkish Football Federation in 1977, before being elected president in 1989, a position he held for eight years.
He then joined UEFA, where he gained the respect of Michel Platini when the Frenchman became president in 2007. He played an integral part in Turkey's successful 2005 Champions League final bid, which was held in Istanbul.
Ted Howard
The deputy general secretary for CONCACAF, Howard could throw his hat into the ring to become the next FIFA president.
The American played football at university level, before he went into coaching.
He was employed as executive director for the North American Soccer League, and also stood as director and group manager for the NBA for 10 years. He was named to the US Soccer Hall of Fame in 2003.
