There were three principal contractors responsible for the building of Louisbourg. In turn, they were: Michel-Philippe Isabeau (1717-1724), Francois Ganet (1725-1735) and David-Bernard Muiron (1736-1745). I here briefly deal with the first of them, Isabeau.
Isabeau was from Paris. We first take note of him, when, in 1717, he sailed into Louisbourg harbour at a time when it was but a crude station, before the times when it was, significantly due to the efforts of Isabeau, the stone citadel and eastern anchor of the French possessions in North America. With Verville's plans in hand, Isabeau came to Louisbourg with a contractor's eye; to see, given the conditions as existed, about the feasibility and connected expenses of bringing the French dream of Louisbourg into being. I can only imagine that Isabeau carried out his inspections and inquiries as he and a cadre of French officers traveled around that summer by boat and by foot; and, that, that autumn, he and his assistants caught the winds in their sea going sailing vessel for a return to France; with his note books full of measurements, calculations and observations. Throughout the following year, Isabeau must have worked with suppliers and crown officials; and, in pulling together all the information he would have needed, placed a bid before those responsible for the building of the new French stronghold, Louisbourg. Isabeau was to sign an agreement with the crown on March 7th, 1719.1
In the spring of 1720, Isabeau came out to Louisbourg to supervise the work. Most of the supplies required were brought over from France. So, too, it is likely, artisans, such as stone masons would have come over with Isabeau each having struck their own contract with Isabeau. As for labour, and much was needed, Isabeau was to depend on the locals and in particular the soldiers of the French garrison. The soldiers after having stood their military duty were free to pick up local work, indeed, in respect to the building of the fortifications, the soldiers were encouraged to get hired on. What contractors, such as Isabeau would do, in order to maximize the return and to preserve cash, would be to pay their help whenever possible, in merchandise (particularly, alcoholic drink).2 The soldier at Louisbourg was usually happy enough with working for stuff, especially when the conversion of full wages was made to merchandise at wholesale rates. This method, however, was not much appreciated by the officer corps at Louisbourg, as they were the ones that ran the retail stores, and, with Isabeau handing out merchandise wholesale; - well, one might imagine the conflict and hot words exchanged during the course of the construction season between Isabeau's people and those in charge of the civil and military matters at Louisbourg.3
On November 20th, 1724, Isabeau embarked on the Victoire so to return to France for the winter. At some point during the sea voyage, Isabeau died. His death was to cause problems, as might be expected when a head of an ongoing and large project dies, problems for both those interested in seeing to the completion of the half built fort and for Isabeau's family. (These problems because of Isabeau's propensity to carry things around in his head instead of keeping written accounts). The family made arrangements with another French contractor, one Francois Ganet, to take over and complete the work on the outstanding contracts with the French crown, on the basis that he should thereafter bear and take any profits from the contracts; the monies owned by the crown to Isabeau for the work completed to his death would be paid to the estate. Ganet like the new broom that he was, found that, in certain aspects of the fortification work, it was necessary to start over again. In time, complaints4 were to be heard about much of the work that had been done and in the result payment to Isabeau's family was held up. It was not until 1731, that Isabeau's family was to get an adjusted payment for the work Isabeau had done.
 This first contract signed in 1719 called the construction of the King's Bastion and Chateau Saint-Louis. The French, already, as of 1717, had started in on the preliminaries, clearing the site, etc. Isabeau was not contracted to build a whole fort but rather specific parts of it; at first we see the King's Bastion and Chateau Saint-Louis, later we see reference to Isabeau's work on the barracks.
 Throughout, however, and it should be noted, Isabeau was to have the confidence and support of Verville, which of course, raised questions as to whether Verille was on the take; and, that maybe so (not surprising given the age) but, Verville was singularly interested in seeing that his fort was built and hectoring Isabeau was contra productive.
 For example in 1727, on account of defects in the construction of the barracks, Verrier made inquiries to see if money due on the building contract should be held back from Isabeau's heirs. (Despatch of June 10th, 1727, as found in Report Concerning Canadian Archives Branch for the Year 1904, Appendix K, p. 92.)