Newsletter operations is the discipline of running profitable email newsletters. It encompasses: growing a subscriber list (content upgrades, referrals, paid acquisition), retaining subscribers (valuable content, consistent schedule), segmenting and personalizing emails, automating sequences, and monetizing (sponsors, affiliate, upsell, paid tiers). Newsletter economics are favorable: $0.05-0.30 per email to send, $1-5 LTV per subscriber monthly. 42:1 ROI makes email the highest-ROI marketing channel. Most revenue-per-subscriber comes from 1-3% of list buying things, but that 1-3% are highly engaged readers.