His work extends beyond market analysis to include contributions to addressing conflict diamonds, promoting Fair Trade practices, and engaging with non-governmental organizations on industry ethics.

[9] He has also promoted the concept of "Fair Trade Diamonds," working to create mining collectives in Sierra Leone and advocating for better labor conditions and equitable distribution of profits.

[14] His work has also included efforts to support artisanal diggers in West Africa, offering them fair prices and advocating for the establishment of "development diamond" labels.

[16][17] He has also been a proponent of viewing diamonds as an investment, emphasizing their durability and the increasing global wealth that drives demand for large stones.

[20][21] Rapaport submitted papers in 2002 and in 2005 criticizing the European Commission's handling of investigations of collusion between De Beers and Russia's state-owned diamond cartel, ALROSA.

He alleged the European body ignored evidence that ALROSA was selling diamonds to De Beers at prices 8 to 20 percent below market value and was aiding and abetting unethical and illegal business practices.

[citation needed] He has also criticized the creation and sale of synthetic diamonds,[22] while acknowledging that they are another commodity that can be sold for whatever value the marketplace deems they are worth.

[28] Rapaport's influence in the industry has also sparked controversy, particularly regarding his commercial price guides, which some see as a step toward the commoditization of diamonds.