Email marketing is considered the best ROI, with and Paid (PPC) following right behind.

How Search ROI Stacks up against the others:

Marketing Tactic Low Value Tactic Strongest TacticGood ROIHard To Gauge

House Email Marketing8% 25% 39% 8%

Search Engine Optimization (SEO) 6% 18% 36% 21%

Paid Search Marketing (PPC)13% 16% 35% 9%

Public Relations 11% 12% 28% 30%

Direct Mail 27% 12% 27% 11%

Online Banners, etc. 43% 3% 16% 13%

Print Advertising 35% 4% 13% 29%

Source: MarketingSherpa, Inc. Search Marketing Benchmark Guide 2008.
http://www.marketingsherpa.com/exs/Search08Excerpt.pdf

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