Purpose: To report the complications encountered during 100 consecutive maxillary sinus augmentations via the lateral window approach and to propose solutions to manage these complications. Materials and Methods: Pretreatment residual bone heights and the presence of septa were recorded. The incidences of any intraoperative or postoperative sinus complications such as excessive bleeding, membrane perforation, infection, wound dehiscence, sinusitis, loss of bone graft, and implant success were reported. Results: This study evaluated 42 men and 44 women requiring 100 consecutive sinus elevation procedures between March 2008 and February 2011. Five intraoperative membrane perforations were noted, and one subsequently developed an active infection (2 weeks after surgery). Eight instances of suppuration were noted, while 10 sites presented with wound dehiscence 1 to 2 weeks after surgery. One example of partial loss of the bone graft 6 months after surgery was identified. Of a total of 151 implants placed in 97 sinuses (one patient with bilateral sinuses and one with unilateral sinus did not complete implant placement), 2 implants presented excessive bone loss prior to uncovering. One implant was removed and one was left submerged. Conclusions: Sinus floor elevation utilizing the lateral window approach is a predictable approach to manage bone volume deficiency in the posterior maxilla for patients seeking dental implant-based treatment. However, complications may include membrane tear, infection, wound dehiscence, loss of graft, and implant failure. It is vital for the clinician to understand how to recognize and solve these complications.