ATHENS — In the year since Greece received its first financial bailout, many things have changed. The country has reduced its budget deficit by 5 percent of gross domestic product. Workers have been hit by wage freezes and pension cuts, prompting a growing popular outcry. The state has revealed for the first time how many people it employs, and tax collectors can now cross-reference swimming pool ownership with declared income to help determine wealth and cut down on rampant tax dodging.

But some things are harder to change. Asked if the state had the means, let alone the will, to properly collect taxes, Froso Stavraki, the head of the collectors’ union, took a long drag from a cigarette. “Huge efforts have been made,” she said in an interview in a cafe here last week. “But no, I don’t think people are afraid of us.”

A year ago, Prime Minister George Papandreou hammered out a $155 billion loan agreement with the European Union, European Central Bank and the International Monetary Fund. In return, Athens pledged a range of structural reforms: cracking down on tax evasion, raising the retirement age to 63 and a half from 61 and a half, limiting early retirement and opening the so-called closed professions whose guilds grant limited access to newcomers.

Now, as he comes back to Greece’s foreign creditors asking for the next $16.8 billion installment of aid — predicated on persuading Greeks to accept more tax hikes, wage cuts and the privatization of more than $71 billion in state assets before 2015 — doubts have emerged about the government’s ability to implement and enforce the measures it has already passed.