With more newsletters more often shown as a key to engagement, INMA has released a report on rapid rise of the form.

Their role as a key tool for publishers among an increasingly complex array of consumer engagement tactics designed to promote frequency of usage among digital subscribers and prospective subscribers is explored in the report.

'How newsletters are redefining media subscriptions' outlines trends and best practices among news media companies aiming to maximise reader revenue through retention and engagement. The report covers key best practices in newsletters from subject matter to style to volume and how best to segment content in a dense ecosystem.

Additionally Rob Josephs of Brightcove and Victoria Fine of Finally provide background and context to why publishers shifted engagement emphasis to newsletters.

Practicalities include emerging business objectives for newsletters and the discovery of frequency as the key metric to predict churn. Commonalities include important differences among global/national brands, digital pure-plays, and metropolitan dailies, and the report also looks at subjects that stand out, including the surprising rise of short-term 'pop-up' newsletters.

It concludes with a deep dive into what the Boston Globe, Financial Times, El País and Cox Media Group are doing with newsletters - media related to metropolitan, global, national, and group.

"It is inside these case studies that the chaos of consumer engagement yields clarity," says INMA executive director and chief executive Earl Wilkinson. "No matter where you are on your digital subscription and consumer engagement journey, the tidbits inside these stories will serve as inspiration and benchmarks - and tease the personalisation revolution that is coming next at media companies."

The report is free to members and US$795 for non-members, including a year's membership. Details from www.inma.org/reports.