Periprosthetic joint infection (PJI) is a significant complication of joint arthroplasty, leading to implant failure and the need for revision surgery. This study aimed to identify current risk factors for PJI after modern joint arthroplasty and to determine the incidence and timing of PJI. Data from 9,245 patients who underwent primary hip or knee arthroplasty between January 2001 and April 2006 were reviewed. PJI developed in 63 patients (0.7%), with 65% occurring within the first year post-surgery. The most common organisms were *Staphylococcus aureus* and *Staphylococcus epidermidis*. Independent predictors of PJI included higher American Society of Anesthesiologists score, morbid obesity, bilateral arthroplasty, knee arthroplasty, allogenic transfusion, postoperative atrial fibrillation, myocardial infarction, urinary tract infection, and longer hospitalization. The study confirmed previously identified risk factors and identified new variables, highlighting the importance of these factors in preventing PJI.Periprosthetic joint infection (PJI) is a significant complication of joint arthroplasty, leading to implant failure and the need for revision surgery. This study aimed to identify current risk factors for PJI after modern joint arthroplasty and to determine the incidence and timing of PJI. Data from 9,245 patients who underwent primary hip or knee arthroplasty between January 2001 and April 2006 were reviewed. PJI developed in 63 patients (0.7%), with 65% occurring within the first year post-surgery. The most common organisms were *Staphylococcus aureus* and *Staphylococcus epidermidis*. Independent predictors of PJI included higher American Society of Anesthesiologists score, morbid obesity, bilateral arthroplasty, knee arthroplasty, allogenic transfusion, postoperative atrial fibrillation, myocardial infarction, urinary tract infection, and longer hospitalization. The study confirmed previously identified risk factors and identified new variables, highlighting the importance of these factors in preventing PJI.