Open investment fonds are financial institutions where potential investors offer various investment options, adapted to their ambitions and preferences. Furthermore, those kind of investments come along as very popular and interesting forms of investment with free financial sources. Prior to that, they first started to come around on financial market at the end of the 90s. Open investment fond in Croatia mark down growth and development, even though they were slowed down few times due to various recessions and crisis, Croatian development oft the fond industry showed constant growth oft he property of the investment fond. Despite various types of open investment fonds, fonds differ due to their structure of investment. It all depends on how much risk comes with the fond, or how much potential yield customer expects or wants to earn. Main and credible measure at the success oft the investment fond is the share growth or also known, yield. It is very important to chose the right moment, as well as the right moment to pull out the sources because the share are very sensitive on changes, that is why it is very important to track their movement and predict their potential sudden changes. Threats int he stake in the open fund investment manifest into alternative types of investment, who bring certain flaws and benefits compare to investment into fonds. That is why they are in different types of economic conditions some of them seem more tempting to the investors because they seem more safe, with higher possibility oft the achieved income.