Advanced scientific editing
If extensive research projects and complex data are to be published, having an “outsider” look through the work can be helpful: Is the text clear and the argumentation logical? Have grammar, spelling, and stylistic rules been adhered to? Is the text too simple or overly demanding?
Your work might be a raw diamond in need of polishing: I revise the style and diction and tailor your text to both the medium and readership.
Editing
Are the facts organized in a way that is didactically reasonable? Are your answers comprehensible, and have you asked the proper questions? I check whether your text is internally coherent, point out faulty logic, and register redundancies.
Most importantly, I pay attention to the language. That is, I guarantee that your style is appropriate and that the text strikes the proper tone with the intended audience.
Re-Writing
There are various reasons why an existing manuscript must be fundamentally rewritten: new experiments or statistical assessments need to be integrated, quotes from the literature quotations have to be updated, or the length and formatting must be made to meet the requirements of a different publication.
Your manuscript does not have to be redone from the ground up, but normal editing isn’t enough. In such cases, re-writing is an alternative.