It can be a logotype aswell as a symbolic logo. If the logo is based as a symbol, it should be possible to put the symbol alone, though it's not a requirement. The symbol should be something that represents our services (water, fire, protection,...) but it can be initials ("PS") aswell.
Our current colors are blue and yellow as shown in attached file. However we would like to keep it, we dont want to limit you in your creativity, so it's primarly up to you. Anyway there should be only two core colors.
The logo has to be memorable, scalable and effective without color.
Unique - express your creativity, we do not want a common logo, think about your design, give us a relevant idea
Balance - everything should match together perfectly
Simplicity - it should be clear and elegant
Tradition - rather than something extra modern we would like something timeless
The logo will be used in either electronic form (web, e-mails) and stationery, thus we would like to see a simple version in colours, in greyscale and version with effects (gradients, gloss, etc. - this one isn't necessary).
In addition we will require the original file (.ai, .svg, .eps,...)
Be creative, good luck.