Strong Finish Copy Editing



Books Strong


Delivering first-class editorial services for three decades: project management; substantive editing, line editing, and copy editing; proofreading; copywriting; and design.


Serving Clients Worldwide

including canada, usa, england,
netherlands, spain, china, and taiwan.


we’ve been going long and strong (for one, two, and even three decades) with most of the following clients:

Featured Title

The Testaments

Strong Finish copy edited and proofread Margaret Atwood’s The Testaments, the internationally best-selling, 2019 Booker Prize–winning sequel to The Handmaid’s Tale.

It’s Heather’s 17th title with the highly esteemed author and recipient of multiple prestigious awards, including the Commonwealth Writers’ Prize, Giller Prize, and the National Book Critics and PEN Center USA Lifetime Achievement Awards. A number of Atwood’s books have been adapted for film, television, and theatre.

“Many thanks are due to … Heather Sangster of Strong Finish, the demon copy editor who picks every nit, including those yet unhatched.” ~ Acknowledgements in The Testaments

“Heather Sangster has been the primary copy editor of my work for the past 25 years and my publications owe a great deal to her services. She is meticulously thorough and thoroughly professional.” ~ Margaret Atwood

In the Press

Heather Sangster/Strong Finish
in The Globe and Mail

Making the Right Calls

Specializing in best-sellers, award-winners, and the development of emerging talent,
Strong Finish delivers the highest calibre of professional editorial services.

We combine classic principles, contemporary sensibilities, insider expertise,
and just the right touch for a signature service with measurably superior results.

In short, whether you’re an author, publisher, or savvy business who
needs editorial support, we can surely help.


manuscript evaluation

Insightful analysis of your content and technique along with effective suggestions in a detailed report.

substantive editing

A big-picture examination to shape structure, credibility, voice, and message.

line / copy editing

A close review for flow, tone, and clarity while correcting mechanical issues.


A meticulous final read for accurate and reliable quality control,
resulting in a polished project.

research & copywriting

A deep dive into fact-checking and supplementary analysis.
Persuasive, natural copy that ignites action.

Portfolio Sample


Let’s Get You There.

Strong Finish's Contact page with a Woman buying a best-selling book.

We’d love to hear about your project and we’re easy to talk to.

So, for a zero-pressure, expectation-free complimentary chat that’s sure to provide clarity, just call:


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