The title of this book is a little misleading. Though that great scourge of the modernists, Umberto Benigni, gets a mention along with sundry other Italian modernists (including, however, George Tyrrell), there is little in the text about modernism as such apart from an illuminating remark in the introduction stating that what characterised many of its proponents was ‘the conviction that action for social justice could not be separated from a profound reform of the Institution’ i.e. the Church. And had I realised that, despite the title appearing to make a general claim to discuss all left-leaning Catholic movements of the last hundred and fifty years or so, apart from a brief excursus on the origins of liberation theology the book focuses exclusively on Italy, I might well have declined the request to review it. I am very glad I did not. I found Saresella's close reading of the ideology of the many – often warring – parties of Italian social Catholicism absolutely fascinating, at least until the final chapter which, because the author brings the story down to mid-2011, rather reads like an over-long newspaper article. I was particularly struck by the influence that was exercised upon social Catholicism in Italy by the writings of Emanuel Mounier and Jacques Maritain. The latter, Saresella notes, was the subject of a denunciation by Cardinal Ottaviani in 1953 in a lecture at the Lateran University because of his defence of the autonomy of politics. Ottaviani of course carried his convictions into the Second Vatican Council, and was only overruled after he had failed to ban from the Council the American Jesuit John Courtney Murray. I was surprised to learn that, as cardinal of Milan, G.-B. Montini, whose father had been a leading light in the Partito Popolare, opposed collaboration at local level between Democrazia Cristiana and the Communists. This, as Saresella remarks, is not the usual understanding of the future pope's role in his Milan diocese. I have only one quibble. The author rightly makes the point that Papa Roncalli's encyclical Pacem in Terris draws a distinction between ‘false philosophy’ (viz. Marxism) and its adherents’ ‘political undertakings’, a distinction which eased the collaboration of left-wing Catholics with socialists. But that apart, she claims that Pope John xxiii did not directly intervene in the debate over the apertura a sinistra. I am not sure what she means by ‘directly’, but many commentators see Mater et Magistra, published two years before Pacem in Terris, as exactly such an intervention, precisely aimed at those senior churchmen who had effectively opposed the apertura a sinistra in an article in the pages of L'Osservatore Romano. As Donal Dorr wrote in Option for the poor, his study of papal social teaching, Mater et Magistra ‘began the process of breaking the long alliance between Roman Catholicism and socially conservative forces’.