I bought this, having enjoyed Pub Walks in Cambridgeshire and Pub Walks in Suffolk, both by Jean and Geoff Pratt.
The walks are set in particularly pretty Northants villages - pubs are well chosen but the walks themselves have been very disappointing. We have now tried about half those in the book and generally find the directions very poor, filled with more personal opinions about the attractiveness of the countryside, whether particular spots would be nice for picnicking and similar irrelevancies than anything useful in the way of landmarks to guide the walker. Have had to completely abandon about three of the 12-15 that we've started - have never had that happen before!
Routes are unimaginative and tend to rely heavily on a rectangular format, with much use of major green lanes/country roads. That said, some good views if you can navigate the way. Would suggest taking an OS map of the area to support the directions given. Would recommend the Cambridgeshire or Suffolk walks from this series instead as an alternative for anyone within reach of those counties.