RSK holds 10th place in Environment Analyst's global environmental consultancy ranking

RSK has kept its place as the world's 10th largest environmental and sustainability consultancy in Environment Analyst's latest global market assessment, the company said, after growing and increasing its global market share in 2025.

RSK said it also recorded the highest growth rate among the established global top 10 in the assessment, Environment Analyst's Global Environmental & Sustainability Consulting Market Assessment, published in October 2026.

RSK has appeared in the same position before. Environment Analyst's press release of 30 January 2025 listed RSK 10th in its ranked top 10, behind TRC Companies in ninth.

Jessica Sparkes, Group Strategy, Communications & Marketing Director at RSK, is quoted on Environment Analyst's December 2025 report page saying the company "greatly values the research and data-supported intelligence gathered by Environment Analyst".

The market

Environment Analyst said the global environmental and sustainability consulting market grew 6.2% to $65.5bn in 2025, despite economic and political instability. North America remained the largest regional market at $31.6bn.

The October 2026 edition analyses 37 firms, which Environment Analyst calls the Global 37. Together they account for 63% of the global market, it said. Antea Group, whose announcement of 13 October 2026 said Antea Group USA was ranked 16th in the same edition, said the ranking is based on firms' environmental and sustainability consulting revenue from financial year 2025.

The market has grown each year across Environment Analyst's recent editions, according to the figures it has published:

Year	Global market size (Environment Analyst)
2023	$54.7bn
2024	$58.8bn
2025	$65.5bn

Environment Analyst's January 2025 release said the market had reached $54.7bn in 2023, marking double-digit growth for the second consecutive year. Its December 2025 edition found growth to $58.8bn in 2024, which it said fell short of its previous forecast. The January 2025 release had forecast $82.8bn by 2028, an expansion it said would require 126,000 additional consulting professionals.

Ross Griffiths, Managing Director of Environment Analyst, said in January 2025 that "our data shows the demand for environmental and sustainability consultancy support has never been stronger".

Concentration and growth areas

Environment Analyst's December 2025 edition said the share of the global market held by the largest 38 firms rose from 52% in 2019 to 65% in 2024. The October 2026 edition, covering a different cohort of 37 firms, gives that group 63% of the 2025 market.

Within the service lines, Environment Analyst said climate resilience and adaptation revenue grew faster than any other environmental and sustainability consulting subservice in 2025. Contaminated site assessment and remediation grew just over 3% in the year.

Looking ahead, Environment Analyst said water and waste management is forecast to add the most absolute revenue to the sector by 2030. Its October 2026 report asks where the next $25bn of growth will come from by that date.

Antea Group described Environment Analyst as having a global membership community of more than 40,000 environmental professionals.

RSK's own announcement gave no revenue or growth figures beyond its statement that it grew and increased market share in 2025.