He is a member of the team of the programme L'Esprit public on France Culture and author of a dozen essays and a musical tale.

He holds a certificate in the legal profession, a DEA in business law from the University of Paris II Panthéon-Assas and graduated from Sciences Po in 2001 (major in finance).

Altermind's unique methodology provides companies with an innovative tool to help them succeed in today's complex and fast-changing business environment.

Since the launch of Altermind, Mathieu Laine has advised several executives of major companies, including Carrefour, Vivendi, Suez, Orange, Crédit Agricole, Danone, Facebook, Airbnb, Prada, AXA, Total, L'Oréal, Nestlé, and the Principality of Monaco.

According to an article in Les Echos, Mathieu Laine proposes with his firm Altermind an innovative model of strategic consulting, by constituting "an ad hoc team for each mission, generally commissioned at the highest level of the company", "by bringing together consultants with academics likely to provide original solutions based on their latest research"; his firm has a network of 300 academics, supplied via "a database developed with in-house AI tools which enables the academic world to be scanned in order to approach new profiles".

Among Altermind's achievements, "to have had the merger between FNAC and Darty accepted by succeeding in including online sales in the reference market considered by the Competition Authority" - the newspaper Les Echos specifies: "professors from Dauphine, HEC, Berkeley and MIT were solicited" - as well as behavioural economics skills and the elaboration of an opinion survey thanks to the participation of more than 22,000 respondents".

Laurent Mignon, chairman of the management board of the French bank, testifies: "Altermind puts people you are not used to seeing in front of you and offers you an astonishing depth of reflection".

In 2002, Laine published an open letter to the then French Prime Minister Jean-Pierre Raffarin about his "cent jours" as head of the cabinet.

[9] Beyond his role as advisor, he is considered a friend of the President of the Republic with full freedom of speech, which has earned him the enmity of some people around the executive.

He denounces excessive interventionism and contemporary socialism, which he identifies as much on the right as on the left, and presents "the power and primacy of freedom" as the salutary path for France.

[11] He considers those regulations to be freedom destroying and demonstrates their inefficiency due to their ‘suffocating’ effects on individuals.

[12] In the Dictionnaire amoureux de la liberté (A Lover’s Dictionnary of Liberty) published in 2013, Mathieu Laine defines freedom as "that deep, individual, cementing feeling of our dignity, the best chance for each person to hope to be and become what he or she is made for.

According to the two authors, the suffocating social policy, the nanny-state, surveillance, characterises this impotent state, which nevertheless wants to be omnipresent in the lives of individuals.

Since Hugues Capet, they list and analyse various recurring facts and phenomena which, in their view, evoke a harmful constant: a mixture of centralism and interventionism at the top of the state.

In Il faut sauver le Monde libre (We must save the Free World), published with Jean-Philippe Feldman in 2019, Mathieu Laine advocates freedom, warning of the dangers that, according to him, jeopardise the first of these values.

Gathering several of his friends around this project, Mathieu Laine entrusted the musical composition to Karol Beffa and brought together artists Patrick Bruel, Renaud Capuçon, Paul Meyer and Edgar Moreau.