Deliverability Community and Expert Resources

When you need to know whether something changed at a mailbox provider this week, or why a filter behaves the way it does, vendor documentation rarely has the answer. The deliverability field is small, and much of its authoritative, practitioner-level knowledge lives on a handful of independent expert blogs.

Three of them are the standard references. Below is what each is known for, and how to use them when you research current events such as policy changes at mailbox providers, blocklist behavior and new authentication standards.

Word to the Wise (wordtothewise.com)

• Who: Laura Atkins (CEO) and Steve Atkins. Laura is a recognized anti-spam veteran with decades of experience tracing internet abuse. Steve covers the deep protocol and technical side. They run a consulting practice (strategy, deliverability, training, mentoring) alongside the blog.
• Coverage: email authentication (SPF, DKIM, DMARC, and emerging work such as DKIM2 and BIMI), sender reputation, inbox placement, B2B deliverability, and explaining technical filtering behavior to non-technical stakeholders. It is strong on why filters behave the way they do, and on the fundamentals of permission and consent.
• Signature resources:
  • The blog at wordtothewise.com/blog/. It has a long-running archive dating from the 2000s era and is frequently cited by the rest of the industry.
  • The Email Best Practices white paper, summarized in WttW Email Best Practices.
  • Explainers on spam traps ("A Brief Guide to Spamtraps", 2011; "What Spamtraps Tell Us", 2025), summarized in Spam Traps.
  • Tools for Email People (tools.wordtothewise.com): practical utilities for email professionals.
  • AboutMy.Email (aboutmy.email): send a test message and get a detailed technical report on its authentication and standards compliance.

Spam Resource (spamresource.com)

• Who: Al Iverson. The site has been running for 24+ years and posts almost daily, which makes it the best single feed for breaking deliverability news: provider shutdowns, filter changes, regulatory and FTC actions, and acquisitions.
• Coverage (from the site map, spamresource.com/p/site-map.html):

• Key URLs of the provider guides: Gmail /2024/02/isp-deliverability-guide-gmail-updated.html; Yahoo, AOL and Verizon /2019/12/isp-deliverability-guide-yahooaolverizon.html; Microsoft /2023/04/isp-deliverability-guide-microsoft-olc.html; Apple iCloud /2020/05/isp-deliverability-guide-apples-icloud.html.
• The site also publishes a newsletter (signup at ml.spamresource.com).

EmailKarma (emailkarma.net)

• Who: Matt Vernhout (Pickering, Ontario, Canada), a long-standing figure in deliverability and email policy. He is particularly strong on Canadian regulation (CASL) and on the work of industry bodies.
• Coverage: email marketing knowledge, industry news, authentication (SPF, DKIM and DMARC), sender reputation, inbox placement, and compliance with changing provider requirements. It publishes several posts a month and has 50+ pages of archives.
• Recurring content: question-and-answer columns on common email marketing questions; the "Email Deliverability Fundamentals" educational series (for example, explainers on SPF); coverage of major announcements from inbox providers (Gmail, Yahoo, Outlook); guest contributions; and curated lists of other deliverability blogs and recommended books.
• The site includes a disclosure about its use of AI ("I use AI to help improve my writing as an editor... all the thoughts and content are mine").

How to use these sources

1. Breaking news, such as "did something change at Gmail this week?": search Spam Resource first, because it posts almost daily. Then read Word to the Wise for deeper analysis, then EmailKarma, especially for Canadian angles.
2. Provider requirements: Spam Resource's ISP Deliverability Guides and its MAGY compliance guide are maintained, dated summaries of the bulk-sender requirements of Gmail, Yahoo, Microsoft and Apple. Always check the post date, and prefer the most recent update.
3. Terminology: Spam Resource's DELIVTERMS series is a glossary you can cite for individual terms.
4. Conceptual "why" questions (why filters behave a certain way, how to reason about permission and consent, what spam traps mean): Word to the Wise is the strongest analytical source.
5. Diagnostics: point senders to AboutMy.Email (from Word to the Wise) for a technical and authentication report on a single message, and to Google Postmaster Tools (Spam Resource has how-tos) for Gmail reputation data at the domain level.
6. These are blogs, so each post is a dated snapshot. For anything that depends on current policy, check the provider's own current documentation before you advise anyone.