To the public he is best known as the author of the Buildings of England series, which is a series of guides to the architecture of every English county. They've been published since 1951. Pevsner edited and wrote most of the series, but they've been revised by others since.
Pevsner began research on the guides in 1945, just as the first Statutory Lists were being drawn up. Their popularity was boosted by the fact that the built environment had become a major concern because of wartime destruction.
As for his selection process, we can see two things. The major emphasis is on medieval, ecclesiastical buildings - churches are the only building type to have their own section. But there is also a consistent attention to Modernist buildings.
From the 1960s onwards, new research began to make the early volumes look unbalanced. Although they covered all periods of architecture, the greatest space had been devoted to medieval churches and modernist buildings. Secular buildings had been given much less attention. The scope has been broadened. There's a greater interest in things like cinemas and Art Deco factories, and recent architecture has to be recorded. The results are more inclusive, but the aim remains the same: to present the public with up-to-date and accessible information about the most significant buildings in the country. A question is how do they define "significant"?
I once read an article that said the Pevsner guides were "the definitive work of British architectural history". Of course, they cannot be definitive. They have no real depth of analysis and they are riddled with mistakes. They are still hugely useful to anyone researching architectural history, but as a starting point for research. To assume that they are definitive because they're full of information is an uncritical assessment. We also have to ask how they inform our understanding.
They represent what's been called "the illusion of inclusion." The format implies that every building of value has been included, and that they haven't been processed at all by Pevsner. In fact, the selection is very exclusive and everything has been filtered through Pevner's own taste and prejudice. In the North East volumes, for example, there's an inordinate attention given to pithead baths, which were not exactly designed as works of architecture, but Pevsner admires them for their functional, utilitarian qualities, which he equates with Modernism.
The books mediate our experience of architecture. A major feature is the "Perambulation", which takes the form of a guided walk around the city. The books are designed to be portable, so what you're supposed to do is follow Pevsner's route and read his commentary as you look at the buildings he's identified. Of course, by doing that, you're seeing them the way he wants you to.
There is also a chronological sequence to the photos. They start with medieval buildings and always culminate with Modernism. So they're like an evolutionary diagram, implying that architecture is progressing towards Modernism, which Pevsner favored. The books are full of value judgements. He did not ignore older buildings (medieval or Victorian), but was committed to "the style of our time." The philosophical basis of Modernism was the idea of the zeitgeist, which is a German word meaning "spirit of the age." This is the notion that culture must reflect its own time. That includes architecture. With this in mind, Pevsner believed it was no longer valid to build in historical styles like Gothic or Classical as the Victorians had done. Instead, Modernism was the only viable style, or "style of the times," as he called it.
Pevsner used various tactics to justify Modernism. For example, he argued that Modernism was consistent with existing British traditions. His project in Pioneers was to create a pre-history for Modernism to justify its use. In the 1920s and 30s, the British architectural establishment viewed Modernism with suspicion - partly because it was European in origin, and was associated with Germany. Pevsner was trying to show that Modernism was not as alien as some people in Britain thought.
There is currently a lot of interest in Pevsner. There is now a website and a cd-rom version of the guides available. Recently there has been a rash of documentaries reassessing Pevsner. Gavin Stamp, one of the key figures in the Twentieth Century Society, did one on Pevsner's coverage of Liverpool. The Victoria and Albert Museum held a conference entitled "Pevner"s Buildings of England' between 13-14th July 2001.