Start with North of Boston. It is the second collection, not the first, and it is where Frost found the thing that makes him worth reading in bulk — long dramatic poems in blank verse, spoken by New England farmers, in which almost nothing is stated and everything is implied. "Mending Wall", "Home Burial" and "The Death of the Hired Man" are all here, and they are nothing like the Frost of the greeting cards.
The chronological instinct says begin with A boy's will, and that is the weaker choice. It is apprentice work: pretty, derivative of the Georgians, and giving little sign of what came a year later. Read it second, as evidence of how fast he changed.
The middle books, which are the essential ones
Mountain Interval holds "Birches" and "The Road Not Taken" — the latter being the most widely misread poem in American literature. Most critics read it as a wry joke about the stories we tell afterwards about arbitrary choices, and the collection's other poems make that reading much harder to avoid.
New Hampshire is the first of his Pulitzer collections and contains "Stopping by Woods on a Snowy Evening" and "Fire and Ice". It is also where the long philosophical title poem shows his other mode, chatty and argumentative, which the anthologies never print.
West-running Brook is shorter and darker, and it holds "Acquainted with the Night". This is the point at which readers who thought Frost was a nature poet usually revise the assessment.
The late books
A Further Range is the most political and was the most attacked on publication; the criticism, from the left, was that he had turned reactionary, and that dispute has never really been settled. It also contains "Design" and "Provide, Provide", which are as bleak as anything he wrote.
A witness tree is the last strong collection. Steeple bush is thinner but holds "Directive", which several critics rate among his best. In the clearing was published at the very end of his life and is generally regarded as slight — read it for completeness, not for the poems.
The prose and the letters
Robert Frost on writing collects his statements on craft, including the essays on the sound of sense and on the sentence as a unit of tone. If the dramatic poems in North of Boston interest you, this is the book that explains what he thought he was doing in them.
Selected Letters of Robert Frost is where the private voice is, and it is markedly less genial than the public one.
The biography, and the fight about it
Robert Frost a Life by Jay Parini — published as Robert Frost: A Life — is the accessible modern account. It exists in large part as a corrective. The authorised three-volume biography by Lawrance Thompson, which dominated Frost's reputation for decades after his death, presented him as vain, cruel and manipulative, and that portrait shaped how a generation read the poems. Parini and others have argued it was distorted by Thompson's own long, difficult relationship with his subject. Both accounts are still in circulation and both are still defended; you should know the argument exists before you take either as the life.
Where to stop
North of Boston, Mountain Interval and New Hampshire are the core, and a reader who does only those three has the poet. A collected edition is the cheaper purchase, but reading the books as books — in their published groupings, with the weaker poems left in — is the whole point of doing it this way. The full sequence is on the path below, and there are more poetry paths on our subject page.
Follow the full ordered path here: Robert Frost in Order: Reading the Collections, Not the Anthology Pieces.