Reading the label is foundational to good consumerism, but the meaning behind the words can be elusive.

Organic. Fairtrade. And, most recently, the blue check-mark label, with “Certified Sustainable Seafood” printed on it, along with the website (www.msc.org) for the Marine Stewardship Council, a London-based nonprofit.

That one’s in the news because of a recent announcement by the Hawaii Longline Association that its products qualified for the globally recognized certification from the council. The review process took 16 months, according to the association, but not everyone is ready to take the credential at face value.

Under the council’s rules, the longline association will have to undergo an annual audit to document that its products are meeting benchmarks for resource management. To get the label, products have to trace back to a source fishery that meets the council’s standards: sustainable fish stocks, with enough fish left in the ocean; minimizing environmental impacts; and management practices responsive to changing environmental conditions.

Association officials have said its fleet has switched to fishing gear and methods that promote shark conservation, to name one example.

Still, critics of the association, including Hawaii officials with the environmental advocacy group Earthjustice, cite other examples from longline fisheries history, with fisheries causing harm to sea turtles and other marine species. They also question the council’s independence in that a fee ranging from $20,000 to $100,000 is charged to cover expenses for auditing, inspections and other tasks.

The issue drew the attention of Netflix, which spotlighted it in the documentary “Seaspiracy” last year. The core assertion of the film, that too many certified fisheries have high levels of protected species caught in their nets, is contested by the MSC.

Defenders say in the absence of proper governmental oversight, having sustainability certification in the realm of the nonprofit sector is better than nothing. That may be so, but short of buying from a fishing operation they know to be responsible, it’s impossible to have certainty.

Most people don’t give this much thought — they shop by price — but those who do should be aware of the limitations of labeling and may have more checking to do on their own.