Though it was challenging to follow the progress of the children once they left primary school, concrete results can be seen.

UNESCO: Country Profile: Nicaragua

The use of concrete imagery is often a primary reason why someone remembers one message over another.

FORBES: Tattoo This Message On Your Brain

They have a primary and a secondary containment structure, both made from thick reinforced concrete, to protect against the release of radioactive materials.

FORBES: Explainer: What Caused The Incident At Fukushima-Daiichi

It will serve as the primary "gateway" to the underground area where the names of the lost are chiseled into concrete.

CENTERFORSECURITYPOLICY: The great Ground Zero heist

But profits and other quantifiable factors now serve as a measure, a concrete, irrefutable tool for assessing the extent to which leaders are being effective in doing their two primary jobs, growing their people and thereby achieving excellence.

FORBES: The New Kind of Leadership for Tomorrow's Leaders