ERM is organized into regional divisions which each have their own cultures, as do the offices within the divisions. Don't think that an openness to flexible work schedules, working from home, or commitment to sustainability is the same in every office; roughly, they mirror the country's regional cultures or are a direct expression of the individual office's senior partner's or office manager's personal philosophy. As with every environmental consulting company I have worked for, there is no such thing as technical training on company overhead - the business model is for junior employees to self-train on the client's dime with low billable rates, or on their own time after 40 hours of billable work per week. When a project is managed well, there is sufficient cost built in for training. Inevitably, projects are not managed well, budgeted poorly, or aggressively priced to remain competitive, leaving 1) junior consultants with few billable hours to produce a deliverable using a very limited skill-set, 2) mid-level consultants and project managers with no billable hours to correct mistakes and struggle to deliver a high-quality deliverable, and 3) partners to respond to staff's high turnover, burnout and dissatisfaction with work/life balance, and client's dissatisfaction with low-quality and late deliverables. Alas, no matter how many exit interviews received, nothing is done to make the investment to adequately train junior employees or reduce mid-level burnout.
The advice then is to choose carefully. First, an office with a culture that reflects your own priorities and desired work experience. Second, as much as you are able, nurture internal relationships to participate in projects with managers and partners that have a track record for winning and producing the high quality work that you are interested in, with an ample margin in the budgets to allow your own development without resorting to excessive work hours for self-education.
Finally, for those interested in developing business services that rely on any capital more significant than a step ladder, beware. Company management has no appetite for taking on capital (i.e., equipment and supply) costs, an unrealistic approach to ROI, and no mechanisms to realistically manage capital (e.g. an internal cost center).