The Premier League has welcomed some incredible players over the last 10 years.
Determining who is "the best" will yield different results for different people, depending on what kind of criteria you look for in the perfect footballer and, of course, which club you support.
For the purposes of this slideshow, we focus on the players who have impressed from the off and/or had a direct impact on the amount of success and silverware of their respective clubs. We've also included some names who simply represent great value for money.
Beginning in 2003/04 with a certain Mr Ronaldo, here's a decade of the Premier League's best transfers.
Agree with the choices? Disagree? Let us know below!
There can really only be one choice for the best Premier League buy of the 2003/04 season—Cristiano Ronaldo.
As the story goes, Manchester United's players urged their then-manager Sir Alex Ferguson to sign Ronaldo after playing against the young Sporting Lisbon winger in a pre-season friendly in 2003.
"They wouldn't shut up about it," Ferguson told the Daily Mail, "They just kept telling me to sign him. In truth. I had realised that night that Ronaldo's secret was now out. We had to get it done."
An 18-year-old Ronaldo put pen to paper at Old Trafford for £12.24 million. It turned out to be a fantastic piece of business as the young winger matured into one of the world's best players.
After appearing in 292 games and scoring 118 goals for the Old Trafford side, the Portugal international could count three Premier League titles, a Champions League trophy and an FA Cup among his haul of honours with the club. Ronaldo was sold to Real Madrid in 2009, for £80 million.
Claude Makelele swapped Real Madrid for Chelsea in the summer of 2003. Brought into the side by Claudio Ranieri, Makelele went on to become one of the Blues' most influential players under Jose Mourinho.
When the Stamford Bridge-bound midfielder departed Madrid, club president Florentino Perez said, via Chelseafc.com, "We will not miss him, his technique is average, he lacks speed and skill, his distribution goes backwards or sideways. New players will arrive to make us forget Makelele."
The French international went on to win two league titles, an FA Cup and two league cups with Chelsea over a five-year period.
For his part in guiding Chelsea to their first Premier League win in 50 years, Didier Drogba stands out as the best Premier League buy of the 2004/05 season.
The Ivorian striker swapped Ligue 1 side Marseille for Stamford Bridge for £26 million and he proved to be worth every single penny by scoring 157 goals during his time with the club.
In addition to three top-flight titles, Drogba also won four FA Cups, two league cups and the Champions League.
Wayne Rooney's much-talked about move from Everton to Manchester United made him the most expensive teenager in British football history.
In his first season at Old Trafford, Rooney was voted PFA Young Player of the Year and in subsequent seasons went on to win a long list of silverware that includes a Champions League trophy, five Premier League titles and two League Cups.
Petr Cech, still going strong with the team that he joined from Rennes in July 2004, has been an outstanding player for Chelsea. The goalkeeper has lifted three Premier League trophies, the Champions League and Europa League, not to mention four FA Cups.
At little over £11 million, Cech was a fantastic piece of business.
While not in the same silverware stakes as the names above, Xabi Alonso's arrival at Anfield in 2004 cannot be underestimated. The Spaniard was brought to Liverpool by Rafa Benitez for £14 million, a snip for someone who went on to be such an important player in the side.
Alonso played over 200 games for Liverpool, where he won both the FA Cup and Champions League. The midfielder's absence was sorely felt when he opted to swap Merseyside for Madrid in 2009 and some would say that the Reds have never found a replacement for the midfielder.
Nemanja Vidic, at his peak, was one of the best central defenders in the world.
In January 2006, the then-24-year-old was snapped up from Spartak Moscow for a reported £7 million, with Sir Alex Ferguson telling MUTV (via BBC Sport), "Good defenders win you things. This lad is really natural and athletic. You need good defenders and that is exactly what this lad is."
The United manager wasn't wrong—Vidic went on to captain United and has made just under 300 appearances for the side. He can count five league titles, three League Cups and the Champions League among his collection of silverware.
Michael Essien comes in as a close second. Chelsea, who were awash with new money from owner Roman Abramovich, were buying legions of new players—including the Ghanaian international.
When he made the switch from Lyon to Chelsea, Essien became the most expensive African player in history. He made over 250 appearances for the Blues and was, at one time, one of the most complete midfielders in Europe before injury started to hamper his career.
Four FA Cups, a Champions League trophy, and two Premier League titles are just a few of the honours Essien amassed at Stamford Bridge.
Edwin van der Sar also deserves a mention as one of the best transfers of the season—certainly one of Sir Alex Ferguson's best signings of the past decade. The Dutchman finally filled the void left by Peter Schmeichel's departure in 1999, and he has a bulging trophy cabinet to show for it.
Mikel Arteta also made quite the impact when he signed for Everton in 2005/06. The former Rangers and Real Sociedad man joined the Toffees for just £2.8 million, as reported by Dominic Fifield in the Guardian, and became a crowd favourite at Goodison Park.
The Spaniard does not have any silverware to show for his time on Merseyside but his creativity was key in getting the side within a whisker of Champions League qualification. Arteta's performances saw him voted as Fan and Players' Player of the Season in his first term with the club, as seen on Evertonfc.com.
No matter what you think of Ashley Cole, Chelsea's acquisition of the left-back for £5 million (plus William Gallas to Arsenal) was a superb piece of business in 2006.
Considered by many as one of the best full-backs of his generation, Cole has made well over 300 appearances for the Blues, where he has won a considerable amount of silverware, including four FA Cups, the Champions League, Europa League and Premier League.
Cole, now 33, has only just started slowing down after spending almost eight years at Chelsea.
Regardless of recent inconsistencies in his form, Manchester City goalkeeper Joe Hart is still considered one of the top-flight's best.
His move from Shrewsbury Town to Manchester in 2006 was quite the coup—the then-England under-19 international costing just £600,000.
As he's matured, Hart has established himself as a top-class keeper and has been a key part in City's revival of recent years.
Carlos Tevez must also be considered as one of the signings of the season. It was West Ham who brought the striker to the Premier League from Corinthians, along with Argentina teammate Javier Mascherano.
Tevez may not have won silverware with the Hammers but his goal—scored in a 1-0 win against Manchester United on the final day of the 2006/07 season—kept the London side in the Premier League. Tevez went on to play for United, City and now Juventus.
Fernando Torres' first season in English football was nothing short of spectacular.
Rafa Benitez signed the striker in the summer of 2007, for a fee in the region of £20 million. The 23-year-old Spaniard took no time to settle in, scoring 33 goals (in all competitions) in his debut campaign.
The following season he came third—behind Lionel Messi and Cristiano Ronaldo—in FIFA's World Player of the Year awards and in January 2011, he was sold to Chelsea for the princely sum of £50 million.
Despite his transfer to Stamford Bridge, Torres will always be held in very high regard at Anfield.
Tottenham Hotspur signed a 17-year-old Gareth Bale from Southampton in 2007. The Welshman didn't make an immediate impact at White Hart Lane but went on to become one of Spurs' most important players in recent seasons—helping the club to its highest-ever points tally in 2012/13.
Bale made Torres' Chelsea transfer look like small-fry when he put pen to paper with Real Madrid last summer, to the tune of £85.3 million.
Everton fans would point towards the 2007 arrival of Leighton Baines as one of their best signings in recent years. Almost into his seventh year at the club, the unassuming left-back has made 260 appearances for the Toffees, scoring 25 goals along the way.
Vincent Kompany has proved to be one of Manchester City's best-ever signings, never mind the last 10 years.
Mark Hughes brought the then-22-year-old to City in August 2008 and the Belgian defender went on to captain City to their first league title in 44 years.
In 2011 and 2012, Kompany was named in the Premier League Team of the Year and was voted Premier League Player of the Season in 2012.
It was not a vintage year for Premier League buys but one other player who merits mention would be Luka Modric, who switched from Dinamo Zagreb to Tottenham Hotspur in summer 2008.
The Croatian was bought by Juande Ramos who deployed him as a defensive midfielder, but he really blossomed under Harry Redknapp, who used him in a more creative role. Named Spurs' Player of the Year in 2010/11, Modric made 160 performances for Spurs before being sold on to Real Madrid in 2012 for £30 million.
With the benefit of hindsight, Arsenal's persistence in signing Aaron Ramsey has really paid off. In 2008, Arsene Wenger managed to sign the 17-year-old from Cardiff City, for just £5 million. As reported on BBC Sport, Manchester United and Everton also wanted to sign the highly-rated teenager.
After making a bright start to his Arsenal career, Ramsey had to fight his way back from a double leg break in 2010. This season, he has been one of the Gunners' standout players.
The most memorable transfer of 2009/10 was Cristiano Ronaldo's departure from Manchester United to Real Madrid.
Wesley Sneijder, Kaka, Xabi Alonso, Arjen Robben and many more were on the move that season yet, back at home in the Premier League, there were not many truly earth-shattering moves.
One transfer that stands out was Gareth Barry making a switch from Aston Villa to Manchester City for £12 million, as seen on BBC Sport.
Bought in the same summer as Carlos Tevez, Emmanuel Adebayor and Joleon Lescott, who each cost double the price of the former Villa captain, Barry did not arrive with huge fanfare.
Yet the midfielder's consistent, "Mr Reliable" performances played a key role in winning City the Premier League title in 2011/12. Barry also won the FA Cup, one season after signing for the Manchester side.
Tevez, too, was a huge signing by Mark Hughes. After winning consecutive league titles with United in the red half of Manchester, he made the switch to Eastlands for £25.5 million.
Displays of petulance and famously going AWOL halfway through the season (as reported by Chris Wheeler in the Daily Mail) left a bitter taste in the mouth for City fans. Nevertheless, 73 goals in 148 games, a top-flight title and the FA Cup are not to be sniffed at.
As more times passes, Liverpool's £22.7 million outlay for Luis Suarez looks like more and more of a bargain.
Controversy aside, he's an incredible player. A striker with a skill set so complete he holds his own alongside Cristiano Ronaldo and Lionel Messi in discussions about who is currently the best in the world.
The numbers say it all: in 114 games for Liverpool, the Uruguayan has scored 73 goals. He has also bagged 40 assists.
Great for Reds fans, terrifying for supporters of rival teams.
If 2009/10 was meagre in its transfer offerings, 2010/11 was a feast.
Manchester City went great guns by recruiting Yaya Toure, David Silva and Mario Balotelli, among others, over the course of the season. Toure and Silva are currently both still huge players for the club, whereas Balotelli—who put away 30 goals in 80 games for the Citizens—made his own, unique, impression on the side.
Across town, Manchester United welcomed Javier Hernandez to Old Trafford for the bargainous fee in the region of £6-8 million. The Mexican has scored 55 goals for the club and has won two Premier League titles.
In the capital, Laurent Koscielny was snapped up by Arsenal from Lorient for just £8.5 million—the Frenchman has established himself as one of the best centre-backs in Europe of late and has been attracting admiring glances from the likes of Barcelona and Bayern Munich, as reported by Jim van Wijk in the Daily Mail.
At Chelsea, Ramires arrived from Benfica for a fee is the region of £17 million. "He is a fantastic player," then-Chelsea boss Carlo Ancelotti told BBC Sport. "He will be the future of the Brazil national team and I hope the future of Chelsea."
Ancelotti's words proved true as the Brazilian international has become a vital player for the Blues, winning the FA Cup, Champions League and Europa League in his three years at Stamford Bridge.
Sergio Aguero's first season in English football was about at perfect as it gets. The Argentina international decided that no "transitional period" would be necessary as he slotted away 23 goals in his debut Premier League campaign.
The most important of those goals came in City's last game of the 2011/12 season, when Aguero scored against Queens Park Rangers on the final day—sealing the win that gave the Citizens their first league trophy since 1968.
The striker has scored a total of 66 goals for the Manchester club and looks set to reenact his prolific spell with Atletico Madrid—where he notched 100 goals in 230 games.
Chelsea's Juan Mata proved to be an incredible buy from La Liga side Valencia. The Spanish playmaker was voted Chelsea Player of the Year and won the Champions League and FA Cup in his debut season with the London side, proving a steal at £27 million.
In 2012/13, the World Cup and European Championship winner added the Europa League and a second successive Player of the Year title to his already impressive honours list.
Robin van Persie, in the face of tough competition, must get the nod as the best buy of the 2012/13 season.
Without the Dutchman's 26 top-flight goals and 15 assists, it's hard to imagine that Sir Alex Ferguson's side would have won their 20th Premier League title last term.
United signed the striker from Arsenal for £24 million. He has scored 40 goals in all competitions since putting pen to paper in August 2012.
However, the 27-year-old made an instant impact with Michael Laudrup's side, where he has scored 28 goals in 62 games. Michu also lifted the League Cup in his first season at the Liberty Stadium—the first time the Swans have won the trophy in the club's history.
Like Swansea, Liverpool picked up another well-priced attacking midfielder in Philippe Coutinho—the Brazilian joining the Anfield side from Inter Milan for just £8.5 million. Coutinho, like fellow 2012/13 buy Daniel Sturridge has been a revelation for Brendan Rodgers' resurgent team.
Elsewhere, Chelsea did very good business by bringing in Oscar and Eden Hazard from Internacional and Lille, respectively.
And finally, beyond the last 10 years, let's take a look at the current season:
There is still a lot of football to be played this term but at the midway point, Alvaro Negredo looks like one of the best buys of 2013/14.
The former Sevilla man has taken no time at all to adapt to the Premier League, where he has already attained cult hero status with City fans.
In his five months with the club, Negredo has scored 15 goals in all competitions and looks like he will be a key player for years to come.
It was a high-spending summer across Europe and the English top flight was no different. Arsenal broke the bank to bring Mesut Ozil to the Emirates, in a £42 million move that could yet turn into one of the moves of the season.
A little easier on the bank balance was the return of former Gunner, Mathieu Flamini, who returned to North London for free after spending five years in Serie A with AC Milan. He may have cost a lot less but his arrival has been no less important than Ozil's for Arsene Wenger's side.
At Hull City, Tom Huddlestone has been making waves, since making his £5.25 million switch from Tottenham Hotspur. The 27-year-old's formidable performances have been so good for Steve Bruce's side, Spurs must be wondering why they ever let him go.
Elsewhere, Man City also spent big on Fernandinho and Jesus Navas, who could play pivotal roles in winning silverware for Manuel Pellegrini this season. At Chelsea, Willian also looks like he could turn into a key player for Jose Mourinho's side.
With the January transfer window still open for the next few weeks, perhaps the very best signing of the season is yet to be unveiled. Who will it be? Only time will tell.