Immigration
The immigration process at Kiev’s Borispol Airport is now relatively fast and efficient. The slow queues and awkward questions of the past are no longer par for the course. Most officials speak a little English.
Travellers may be asked to prove they have health insurance and if not, will have to purchase a cheap Ukrainian policy. Citizens of the UK, and other countries with reciprocal health agreements with the Ukraine, should not be asked.
Visas for Ukraine
Legislation passed after the Orange Revolution opened up Ukraine to citizens of many developed countries. Citizens of European Union countries, America, and many other developed countries were no longer required to obtain visas to visit Ukraine, provided the duration of stay was less than 90 days. To stay longer, these travellers merely had to exit Ukraine at a border and re-enter.
The pro-Western government of the time hoped that these relaxed immigration requirements would lead to similar regulations for Ukrainian visitors to the EU, US, and elsewhere.
European and other governments never reciprocated and Ukrainians wishing to travel to almost any Western country still have to go through arduous procedures to obtain visas.
Ukraine subsequently reacted to the lack of response from the West and tightened up its visa regulations.
Ukrainian immigration law now states that citizens of the US, EU countries (Germany, France, UK, Italy, Spain, Poland, Netherlands, Portugal, Greece, Belgium etc.), most CIS states, Georgia, Andorra, the Vatican, Iceland, Canada, Korea, Liechtenstein, Switzerland, San Marino, Monaco, Norway, Paraguay, and Japan do not need visas but can only stay for 90 days in a 180 day period (counted from the date of first entry into Ukraine).
Everybody else (including citizens of Australia and Turkey) needs a visa to enter the Ukraine. This must be obtained before travelling from a Ukrainian embassy or consulate abroad.

Reviews / Comments / Additional Information
Never had any trouble entering and only 1 time leaving did they want to check my bags. They were very open honest and even apologetic about having to do so.
Upon leaving, they x-rayed all my bags, but even still, it was nothing compared to entering the US. When I went through US customs, they opened my bags, and swabbed for drugs and explosives.