Tanzania is not a problematic country for women (even those traveling alone) to visit, although the normal precautions should be taken. You shouldn't go anywhere alone at night, and be wary of unsolicited male interest, especially in the coastal resorts, where foreign women looking for sexual adventure have encouraged pestering by local men. This can be dealt with if you are assertive. Women travelers should dress modestly, as Tanzania has a wide range of cultural differences. The islands and the coast are predominantly Muslim, so a modest dress code will help you blend in. Wear skirts or pants that reach below the knee and tops that cover shoulders and upper arms. Avoid see-through or overly tight clothing. In beach areas, where there are a lot of tourists, it's acceptable to wear beachwear, but going topless is considered taboo. Lamu and Zanzibar are particularly conservative, so it's important to heed this dress advice so as not to insult the local people. Most of the women on these islands and much of the Muslim coast wear bui-buis, head-to-toe black Islamic dress. Also be aware that public displays of affection are severely frowned upon in Zanzibar, and previously visitors have been arrested for kissing in public. Local women themselves are highly respected, especially older women, so a sharp word from them will help diffuse any number of situations. On public transport, try to get a seat next to other local women. You may be rewarded with good conversation, too.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.