A resume is paradoxically important and not important.  It's important because it makes you think through your career and analyze what your accomplishments were and how they relate to your next job.  But on the other hand it's not important because 80% of jobs are got through networking where it is the personal relationship that is key not what is written on the page.

Here are the key points to think about when you work on your resume:

A resume is a selling tool not a statement of what you have done.
It must be targeted to the recruiter and employer.
It should include accomplishments.
- Accomplishments are stories with a beginning, middle and end.  The beginning is what I inherited/or the initial status quo, the middle is what I did, and the end is the results.  Many accomplishments only talk about what the jobseeker did without giving the setup and the punchline.
- In your accomplishments use measurable results - include numbers, %.
- Always answer "so what?" when writing your accomplishments.
- I increased turnover by 10% (so what?)
- I increased turnover by 10% so we were the leading company in the industry.
Usually a resume is 2 pages - maybe 3.
It needs to tell enough about you to get an interview but not too much to raise questions and get rejected.  It's an appetizer not the full meal.
It should mirror the job posting and address the key job requirements.
Customize a resume to a particular job when appropriate.
Use the same jargon and key words that the advertisement uses.
Don't include hobbies, personal interests etc.

Do include relevant memberships, professional affiliations etc.
Include Education - colleges (don't include dates as this can date you).
Include relevant Training - courses (external and internal)
Don't include Objective - it ties you to one job, takes up space, and doesn't normally give additional useful information.
Do include a 2-4 line summary of who you and key accomplishments at the beginning of the resume.  This is standard for executive level jobs. 
Double check for grammar and spelling errors.
Don't include photographs and personal information (in US - different in other countries so there follow local customs).
Don't use cute fonts, fancy graphics or colored paper.
Don't save your resume as a PDF save as a Word or other format (RTF). If a recruiter wants to cut and paste from your resume to put into a database they can’t with a PDF.
Use key words if you believe the resume will be scanned electronically.  Key words depend on your industry and the market but could include MBA etc.

Author's Bio: 

David Couper is a career coach and writer who for the last twenty years has worked in Europe, Asia, and in the USA with major organizations including the BBC, Fuji Television, Mattel, Sony, and Warner Bros.

He has successfully coached individuals at all levels including CEOs of major companies wanting a new challenge, frustrated souls wanting to make their dream come true, and front-line employees laid off and desperate to get a job.

David has published seven books. His works on interpersonal skills, counseling in the workplace, and management issues (published by Connaught, Gower, HRD Press, Longman, Macmillan/Pearson Publishing, Oxford University Press) have been translated into Swedish, Polish, and Danish, and published in the UK and the USA.

David has a degree in Communication, a postgraduate qualification in education, is certified in a number of training technologies, and has a Masters in Psychology. He is a member of the American Society of Training and Development, Society of Human Resources Professional, Writers Guild and the British Academy of Film and Television.

He has dual US/UK citizenship and speaks French and Japanese.

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