Danny is a product of Norwich City's School of Excellence and signed for his hometown club in July 1993. Danny attended Sprowston High School which has also produced Paul Clayton , Matthew Wright and myself Steve Whitlam. In fact Danny attended the same scout troop as myself (the 30th Norwich group). Impressing in the Norwich youth team, Danny won England Youth caps and was named as a substitute for the Premiership clash with Everton in November 1994 whilst still 17. He made his full debut on 13th August 1995 against Luton. Playing in a variety of roles in defence (right back, central defender and occasionally on the left), his versatility attracted the attention of Charlton manager Alan Curbishley who was picking a Nationwide League Under 21 side to play against their Serie A counterparts. Danny captained this side. Danny left Norwich having made 73 appearances for the club, scoring once. He has equalled this scoring record for Charlton netting once in just 9 Division One appearances before the 1997/98 season finished.

Charlton's relegation on 16th May 1999 into Division One led to increased speculation that Danny would depart from the Valley to fund the club's attempts to return to the top flight. According to the Evening Standard, West Ham showed an interest but were put off by Danny's £4million rating. Leeds supposedly made a derisory £1million bid for Danny but Charlton held out for 4 times that figure. Their hold-out was backed by Danny's call-up on Sunday 6th June 1999 into the full England squad for the Euro 2000 clash with Bulgaria as a result of injuries and suspensions to the team in their 0-0 draw with Sweden the day before. Leeds persevered and eventually won their man on 16th June 1999.

As stated above, Norwich City made almost £0.8million from Danny's sale as there was a 25% sell-on clause from their sale on March 17th 1998 when Danny Mills joined then fellow First Division side Charlton Athletic for a fee of £350,000. The transfer listed defender was unhappy at the limited number of first team opportunities at Carrow Road and had sought a transfer since December 1997. Gillingham and Millwall had expressed interest on taking Mills on loan but Mike Walker sought a cash injection to fuel new squad additions prior to the transfer deadline day. Mills' arrival at The Valley coincided with a run of form that almost won them automatic promotion into the Premiership. However they had to settle for a play-off semi-final against Ipswich which was won despite Mills being sent off in the first leg. Danny played in the victory over Sunderland at Wembley that took Charlton into the Premiership. He aimed a verbal blast at Carrow Road saying that he had proved them wrong by gaining promotion. This victory was worth an extra £50,000 to City's bank balance.

Danny blasted his first club Norwich after completing his transfer to Leeds. "Norwich have got double now what they got for me when I left and I'm showing a few people there what I can do. Some people at Norwich were pleased to see the back of me because they didn't think I was good enough and I'm delighted to prove them wrong. I've always had belief in myself ad now I'm playing for a top Premiership club. It took me a long time to get out of Norwich and when I did a lot of people thought I wasn't good enough for the First Division. I'm glad they are now eating humble pie".

His move to Leeds ended an excellent season for Danny despite Charlton's relegation. Charlton's fine start to their initial season in the Premiership was credited to Danny's sterling performances in the back four with him winning Man of the Match awards in a number of Sunday papers. He became a regular in the England Under 21 squad. His fine form led to transfer speculation that Spurs were preparing a £2.5million bid for his services. The Daily Mirror reported on 16th November that Sheffield Wednesday were also interested in the impressive Mills whilst the News of the World speculated on 11th March 1999 that Danny was a target for West Ham who would attempt to sign him this summer.

Danny Mills had joined Leeds United on 16th June 1999 for approximately £4million from relegated Charlton Athletic. Then Leeds chairman Peter Risdale said "Danny represents an excellent acquisition. He is one for the future and at an age which fits into the type of young skillful team which we are trying to build at Leeds." Manager David O'Leary commented that he was delighted to get his man "Let's hope he can become a great player for Leeds". Danny himself said "I had a great year at Charlton and I'm very pleased and grateful for what they have done for me but now I have come to a massive club and one that is going from strength to strength. The manager is ambitious and the squad is a good mix of experience and youth." Due to a sell-on clause from Danny's transfer from Norwich to Charlton, the Canaries received approximately £600,000-£800,000 from Danny's move to Elland Road.

Danny initially found in hard to settle in Leeds and had been the subject of many a transfer rumour in his initial months at Elland Road possibly because he is not the typical star player that Leeds would wish to build their team around. Another member of the England management team, Peter Taylor, had also been rumoured to be keen on Danny and was said to have prepared a bid for him on behalf of Taylor's club side Leicester in February 2001. This rumour resurfaced in April 2001 on the Football Transfers website along with suggestions that Danny would head to Goodison Park and join Everton. Teamtalk linked Danny Mills with a return to London on 10th May 2000. Supposedly West Ham manager Harry Redknapp was interested in signing the former Norwich and Charlton defender as West Ham had a problem with their full back position whilst Danny had found it hard to displace Gary Kelly in the Leeds first team.

For a player discarded by Norwich for £250,000, it was galling for the Carrow Road faithful to read that Danny Mills enjoys success with Leeds especially in the UEFA Champions League, and win international honours for England. Danny impressed in Leeds' Premiership season and in their impressive European Champions League campaign against the likes of Barcelona, Lazio, AC Milan and Real Madrid. Sven Goran Eriksson's assistant Tord Grip brought Mills' form to Sven's attention. In May 2001, Danny's form and an injury to Wes Brown of Manchester United saw Danny called up for the full England squad for the matches with Mexico and Greece. He made his international debut as a substitute for Emile Heskey on 67 minutes in the Mexico clash with England won 4-0.

On May 9th 2002, this former Sprowston High School student was included in Sven's final 23 for the World Cup finals in Korea and Japan. Although Mills was blamed for the Swedish equaliser in the opening World Cup clash on 2nd June, he had a solid game and then impressed in the 1-0 victory over Argentina on 7th June. Although England were knocked out in the quarter-finals by Brazil, Danny was ever-present in England's five games and had strong performances in every game and was one of the few players to emerge with credit after the defeat to Brazil.

On his return to England, Danny was soon linked with a £7million transfer to champions Arsenal - a move that could well generate income for Leeds who need to cut their £77m deficit by £15m in the summer of 2002. Failure to agree a new contract saw Mills linked in November 2002 with a £8million move to Middlesboro whose manager Steve McClaren is known by Mills from their England exploits. The following month saw Arsenal linked with a £5million move for Mills to replace Oleg Luzhny. Leeds' financial plight might inspire them to sell Mills.

Poor form in Leeds' pre-season matches saw Danny dropped from Leeds' first game of the 2003/04 season against Newcastle. Mills expressed his displeasure at going from European Championship qualifier appearances to the reserves in mere months. Leeds manager Peter Reid didn't appreciate Mills' point-of-view and allegedly told Mills that he has played his last game for Leeds. Steve Bruce's Birmingham hoped to take advantage of this rift and approached Leeds to take Mills on loan for the 2003/04 season. Middlesboro also expressed interest in a similar loan deal whilst Kevin Keegan's Manchester City have been linked with a £2million transfer bid. Any of these would help Leeds' perilous financial situation! In the end, Danny opted to use the connection he had with England coach Steve McClaren to join Middlesboro on loan for the 2003/04 season with a permanent move following afterwards if all parties agree. In January 2004, Middlesbrough started exploring the possibility of a permanent move for Mills. A figure of £1.5million was said to be too much and allegedly interested Birmingham manager Steve Bruce who might swoop for Mills.No move materialised and Danny continued playing for Boro helping them win the 2004 Carling Cup final against Bolton - this was Boro's first ever piece of silverware in all their history.

Danny was linked with a move to Rangers at the end of March 2004 although Alex McLeish would face competition from Boro and Birmingham. After Norwich's promotion to the Premiership at the end of April 2004, Mills was linked with a return to Carrow Road but this was quikcly dismissed by Nigel Worthington who clearly stated that Norwich could not afford Danny's £40,000 per week wages. He was then linked with Manchester City and Newcastle - with Sir Bobby Robson confirming Newcastle's interest in Mills. "Danny Mills is up for grabs. We are aware he is at the end of a contract with Middlesbrough" (The People, May 16th 2004). Failure to agree terms with either Boro or Newcastle led the Eastern Daily Press to speculate on 12th June that Danny might return home to Norwich although the wage cut required would probably put him off.

In the end, Danny signed for Kevin Keegan's Manchester City on 13th July 2004 on a free transfer, following Smith, Viduka, Milner, Harte and Robinson out of Elland Road. Losing his place to Nedum Onuoha, he was linked by the People on 15th May 2005 with a move to Wigan or Blackburn. He was later linked with a move to newly promoted Sunderland. In February 2006, he was linked by The News of the World with a return to London as West Ham were supposedly interested in him. He told the same paper on 23rd April 2006, that he was looking to leave the club in the summer of 2006 as he had a row with manager Stuart Pearce over the lack of first team action and thought that he had been blamed for Man City's poor form since the New Year. Pearce announced on 26th May 2006 that Mills was free to leave the club.Two days later, the News of the World suggested that Mills might move to Premiership new boys Sheffield United as Mills' home was in Harrogate. On 1st June 2006, Mills was linked with a switch to Aston Villa according to the Daily Express. On 27th August 2006, the News of the World suggested that Blackburn manager Mark Hughes would be making an approach for Mills. Danny joined Hull City on loan on the 14th September 2006. New Leeds boss Dennis Wise was said by the Daily Mail to be targeting Mills, who is on loan at Hull, for a return to Elland Road. Although Mills returned to Manchester City, speculation suggested that he was keen to rejoin Hull on a permanent basis - the sticking point being the £20,000per week cut in wages! Reports on 19th/20th March 2007 suggested that Leeds had made an enquiry to sign Mills on loan to aid their relegation battle. During June 2007, Mills was linked with a move to Scotland to join Rangers.

Despite the arrival of his former England manager Sven Goran Eriksson as Man City boss, Mills was placed on the transfer list on 7th August 2007 along with Ousmane Dabo and Paul Dickov. Despite speculation linking him with Southampton and Hull, Danny rejoined Charlton on 31st August 2007 on loan until the end of December 2007. He made his debut the following day in the 1-0 win at Crystal Palace.

Although Charlton were keen on signing Mills permanently, he blotted his copybook with them when sent off in one of his final games. Returning to Manchester City, he was linked in the papers with Leeds United and Hull City but instead joined Derby County on 4th January 2008 on loan until the end of the season. He made his debut for the Rams two days later in the 2-2 FA Cup draw with Sheffield Wednesday. He was injured in his second game for the Rams and never played again.

Mills was released by Man City on 1st July 2009 and subsequently announced his retirement due to his injuries

In October 2013, Mills was appointed to the FA Commission set up to examine how to improve the national team's fortunes and enable more home grown talent to come through the domestic leagues. Other members of the commission include former England manager Glenn Hoddle, League Managers Association chairman Howard Wilkinson, Professional Footballers Association chairman Ritchie Humpheys, former Crewe manager Dario Gradi and Football League chairman Greg Clarke.