Nearly two-thirds (61%) of marketers say one the biggest challenges of influencer marketing is identifying the relevant persons who can truly help their brand or campaigns, according to a recent report from Augure.

More than half (56%) of marketers say another major challenge is getting the attention of influencers and building interest with them via direct interactions.

Accurately measuring the ROI of influencer campaigns is an additional headache, with 44% of marketers citing it as a significant challenge.

Below, additional key findings from the report, Influencer Marketing Status 2014, which was based on data from a survey of 649 European and US marketers.

What Makes Someone an Influencer? 

• Only 23% of respondents say a well-known celebrity is inherently an influencer.
• Just 9% see Klout as a valid method for defining the influence of a person.
• 79% of respondents say an influencer should "echo"—i.e., be able to mobilize opinion and create reactions when they talk about a specific topic.
• 73% say "exposure" is an important attribute—i.e., the size of the influencer’s community in a specific area.
• 62% cite "share of voice": the influencer’s degree of participation in conversation on a given subject.

How Influencers Are Contacted

• 66% of respondents say email is a suitable and effective channel for contacting influencers.
• 57% say Twitter is a useful channel.
• 52% say contacting influencers via their blogs is effective.

When to Deploy Influencers

• 76% of respondents say turning to influencers when launching a product is "highly strategic."
• 57% say they should be deployed during content promotion and distribution.

Measuring Effectiveness

• 65% of respondents measure influencers' effectiveness by the number of times they are mentioned in blogs or in social media.
• 51% look at the number of times their content has been shared.
• 42% measure effectiveness according to Web traffic being generated.
• Only 31% use business-based criteria, such as the number of sales opportunities created.

About the research: The report was based on data from a survey conducted between December 2013 and January 2014 of 649 European and US marketers (30% B2B-focused, 27% B2C, 24% both).