The Bishops' Church Music Committee has produced this leaflet to make it easier to absorb. It takes the official statement that 'singing at Mass is of great importance' 1 and applies it to the situations in which we find ourselves. Resources of time and people are in short supply in our parishes, and choices have to be made about where to put our energy. It is important to know what to choose, which parts, according to the Church, should be sung so that we can respond to the Word and give thanks to God most worthily. If you ask people what the main sung parts of Mass are, many will say 'the hymns'.
Hymns are all many people experience, so that is a reasonable answer.
It can be a surprise to hear that to sing hymns at Mass is a quite recent development and that you could have a perfectly good sung Mass with no hymns. The five columns are a way of showing this. They serve as a checklist, so that if for instance you are not singing anything in columns 1 or 2 you need to re-assess your priorities. Column 1 shows a Mass with no hymns. Because they allow us to acclaim the presence of Christ in his Gospel and on the altar, at the two most solemn moments of the Mass. Column 2 adds some more pieces to the basic core.