He was a leading member of the Senegalese Democratic Party (PDS) and was considered a protégé of President Abdoulaye Wade, but he subsequently went into opposition and was a candidate in the February 2007 presidential election, coming second place with about 15% of the vote.

[7] Seck was detained in July 2005 for alleged corruption in connection with a road project in Thiès,[8][9] and he was additionally charged with threatening state security.

[15] According to final results released after the presidential election, which was held on February 25, 2007, Seck took second place with 14.92% of the vote, falling far behind Wade, who won a majority in the first round.

A scholarship holder, he joined the preparatory class at the École des hautes études commerciales de Paris (HEC) of the Marcelin-Berthelot high school in Saint-Maur-des-Fossés in France and then in 1983, Sciences Po, in the "Economy and Finance" section.

Idrissa Seck is the founder of the consulting firm GDP INITIATIVES (Global Development for Peace) and ÉPI SA (Epistemon International), an education and health institution.

Idrissa Seck, denounced then President Wade's third term candidacy and ran under the banner of his political party Rewmi.

Intent on defending Senegal against then President Wade from running a third term, Idrissa Seck, presented a united front with all M23 candidates, to support Macky Sall's candidacy.

He explained that he was "responding positively to the President's call" for a "union" to face up to the "challenges of the moment", and mentioned the economic and social crises arising from Covid 19, as well as insecurity in the West African sub-region.

Idrissa Seck resigned as President of the Economic, Social and Environmental Council on April 24, 2023, after declaring himself a candidate in the 2024 presidential election.

On March 24, 2020, Macky Sall launched a wide-ranging consultation of all the country's political forces with a view to achieving national unity in the face of the COVID-19 pandemic.

Idrissa Seck interested in maintaining the health and well-being of the people of Senegal fully endorsed Sall's initiative to create an emergency plan called Force Covid-19.

In 1988, then 29 years old, Idrissa Seck was appointed Campaign Director to Abdoulaye Wade, the Presidential Candidate of the Senegalese Democratic Party[8].

On July 23, 2005, Idrissa Seck, was placed in police custody and charged with « undermining state security » for unmentioned acts and incarcerated in the central prison of Dakar.

Prime Minister Macky Sall made public the report of the State General Inspectorate which alleged Idrissa Seck, exceeded the budget of a construction site in Thiès and awarded a contract without having the right to do so.

On July 31, 2005, the parliamentary majority voted to indict Seck, as well as that of the Minister of Housing, Salif Bâ, before the High Court of Justice for « serious irregularities in the process of concluding public contracts ».